Yale MPB045VG Guide

Maintenance
CONTROLLER
DIAGNOSTICS
MPB045VG [A245]
PART NO. 550095689 9000 YRM 1671

Safety Precautions TROUBLESHOOTING
PROCEDURES
• The Service Manuals are updated on a regular basis, but may not reflect recent design changes to the
product. Updated technical service information may be available from your local authorized Yale® dealer.
Service Manuals provide general guidelines for maintenance and service and are intended for use by
trained and experienced technicians. Failure to properly maintain equipment or to follow instructions
contained in the Service Manual could result in damage to the products, personal injury, property damage
or death.
• When lifting parts or assemblies, make sure all slings, chains, or cables are correctly fastened, and that the
load being lifted is balanced. Make sure the crane, cables, and chains have the capacity to support the
weight of the load.
• Do not lift heavy parts by hand, use a lifting mechanism.
• Wear safety glasses.
• DISCONNECT THE BATTERY CONNECTOR before doing any maintenance or repair on electric lift trucks.
Disconnect the battery ground cable on internal combustion lift trucks.
• Always use correct blocks to prevent the unit from rolling or falling. See HOW TO PUT THE LIFT TRUCK
ON BLOCKS in the Operating Manual or the Periodic Maintenance section.
• Keep the unit clean and the working area clean and orderly.
• Use the correct tools for the job.
• Keep the tools clean and in good condition.
• Always use YALE APPROVED parts when making repairs. Replacement parts must meet or exceed the
specifications of the original equipment manufacturer.
• Make sure all nuts, bolts, snap rings, and other fastening devices are removed before using force to
remove parts.
• Always fasten a DO NOT OPERATE tag to the controls of the unit when making repairs, or if the unit needs
repairs.
• Be sure to follow the WARNING and CAUTION notes in the instructions.
• Gasoline, Liquid Petroleum Gas (LPG), Compressed Natural Gas (CNG), and Diesel fuel are flammable.
Be sure to follow the necessary safety precautions when handling these fuels and when working on these
fuel systems.
• Batteries generate flammable gas when they are being charged. Keep fire and sparks away from the area.
Make sure the area is well ventilated.
NOTE: The following symbols and words indicate safety information in this man-
ual:
WARNING
Indicates a condition that can cause immediate death or injury!
CAUTION
Indicates a condition that can cause property damage!
On the lift truck, the WARNING symbol and word are on orange back-
ground. The CAUTION symbol and word are on yellow background.

©2019 Yale Materials Handling Corp.
TABLE OF CONTENTS
SECTION 9030 - ELECTRICAL SYSTEM
Group 03 - General Maintenance and Diagnostic Data ..........................................................................9030-03-1
Group 20 - Diagnostic Trouble Codes .................................................................................................... 9030-20-1
This section is for the following models:
(MPB045VG) [A245]
CONTROLLER DIAGNOSTICS Table of Contents
i

How To Use This Troubleshooting Manual
GENERAL INSTRUCTIONS AND SAFETY
INFORMATION
WARNING
DO NOT add to or modify the lift truck. Any modifi-
cation that affects the safe operation of the truck
cannot be undertaken without written authoriza-
tion of the Yale company.
Any change to the lift truck, the tires, or its equip-
ment can change the lifting capacity. The lift truck
must be rated as equipped and the nameplate
must show the new rating capacity.
WARNING
The technician must be aware of, and follow, all
general safety precautions that are published in
the Operating Manual and that are posted as Safe-
ty Decals on and in the lift truck.
Before starting, the technician should be familiar with
certain policies, requirements, and instructions used in
the troubleshooting procedures. Using the
troubleshooting procedures correctly helps the
technician to perform the procedure safely and
prevents damage to the machine and support
equipment.
HOW TO USE DIAGNOSTIC
TROUBLESHOOTING MANUAL
Manual Layout:
Section: This manual consists of one section which is
further divided into groups.
• 9030 – Electrical System
Groups: The 9030 Electrical System is divided into
two groups that identify specific electrical
troubleshooting procedures.
• 03 – General Maintenance/Diagnostic Data
The General Maintenance and Diagnostic Data
group includes general troubleshooting,
discharging the capacitors, basic electrical
troubleshooting, multiplexing, User Iterface, and
status codes and descriptions.
• 20 – Diagnostic Trouble Codes
The Diagnostic Trouble Codes group includes
all troubleshooting procedures for status codes
reported by a given Node or system.
For a listing of all Diagnostic Trouble Codes and
descriptions, see the section of this manual.
GENERAL INSTRUCTIONS
1 Become familiar with the content, layout, and
access provisions of data in this manual. This
will improve your efficiency and decrease the
time required to resolve the problems.
2 Once you begin a troubleshooting procedure, do
not skip steps.
3 If you reach the end of a procedure without
resolving the problem and you are not directed
to another procedure contact Resident Service
Engineering through the Contact Management
System.
4 Do not limit yourself, remember to apply your
own experience and knowledge to assist in
resolving the problems, but do not compromise
safety in doing so.
5 Most of the cross-reference data in the manual
will be electronically linked for rapid and easy
access. Use the links wherever the cursor
highlights an item as a linkable option.
CONTROLLER DIAGNOSTICS How To Use This Troubleshooting Manual
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Confidential/Proprietary - Do Not Copy or Duplicate iii

SECTION 9030
ELECTRICAL SYSTEM
TABLE OF CONTENTS
Group 03 General Maintenance and Diagnostic Data
General Troubleshooting ........................................................................................................................ 9030-03-1
Discharging the Capacitors .................................................................................................................9030-03-1
Electrical Test Equipment ....................................................................................................................... 9030-03-3
PC Service Tool .............................................................................................................................. 9030-03-3
Digital Multimeter (DMM) ................................................................................................................ 9030-03-3
Jumper Wires, Test Leads, and Test Lights .................................................................................... 9030-03-3
Basic Electrical Troubleshooting .............................................................................................................9030-03-3
Electrical Checks ................................................................................................................................ 9030-03-3
Voltage Checks ...............................................................................................................................9030-03-3
Amperage Checks .......................................................................................................................... 9030-03-5
Resistance Checks ......................................................................................................................... 9030-03-5
Contactor and Contactor Coil Checks ............................................................................................ 9030-03-5
Lift and Lower Switch Check .......................................................................................................... 9030-03-5
Multiplexing .............................................................................................................................................9030-03-6
Multiplexing and the CANbus ............................................................................................................. 9030-03-6
Troubleshooting the CANbus ..........................................................................................................9030-03-6
Troubleshooting the Tiller Control Card Termination Resistor ........................................................ 9030-03-7
Troubleshooting the Traction Controller Termination Resistor ........................................................9030-03-7
User Interface .........................................................................................................................................9030-03-7
User Interface, Setup, and Troubleshooting ....................................................................................... 9030-03-7
Status Code Indication ....................................................................................................................9030-03-7
Parameters ......................................................................................................................................... 9030-03-7
Speed Steering Reduction ..............................................................................................................9030-03-8
Traction Steering Decel Ramp ........................................................................................................9030-03-8
Response-Full Accel Rate HS ........................................................................................................ 9030-03-8
Response-Full Accel Rate LS .........................................................................................................9030-03-8
Response-Low Accel Rate ............................................................................................................. 9030-03-8
Response-Neutral Decel Rate HS .................................................................................................. 9030-03-8
Response-Neutral Decel Rate LS ...................................................................................................9030-03-8
Fine Tuning-Partial Decel Rate .......................................................................................................9030-03-8
Fine Tuning-HS (High Speed) .........................................................................................................9030-03-8
Fine Tuning-LS (Low Speed) ..........................................................................................................9030-03-9
Fine Tuning-Reversal Soften .......................................................................................................... 9030-03-9
Fine Tuning-Max Speed Accel ........................................................................................................9030-03-9
Fine Tuning-Max Speed Decel ....................................................................................................... 9030-03-9
Interlock Timeout ............................................................................................................................ 9030-03-9
Mode (1 through 3) -Max Speed .....................................................................................................9030-03-9
Mode (1 through 3) -Max Accel ...................................................................................................... 9030-03-9
Mode (1 through 3) -Walk Accel ..................................................................................................... 9030-03-9
Mode (1 through 3) -Max Decel ...................................................................................................... 9030-03-9
Mode (1 through 3) -Neutral Braking .............................................................................................. 9030-03-9
Mode (1 through 3) -Max Braking ................................................................................................... 9030-03-9
Max Speed TM2 ............................................................................................................................. 9030-03-9
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TABLE OF CONTENTS
Max Accel TM2 ............................................................................................................................... 9030-03-9
Max Decel TM2 ...............................................................................................................................9030-03-9
Neutral Braking TM2 .......................................................................................................................9030-03-9
Max Braking TM2 ............................................................................................................................9030-03-9
Turtle Alarm enable .......................................................................................................................9030-03-10
Quick Lift Window ......................................................................................................................... 9030-03-10
Initial Lift Interval ...........................................................................................................................9030-03-10
Full Lift Interval ............................................................................................................................. 9030-03-10
Lift Run Time .................................................................................................................................9030-03-10
BDI Warning (Lift Lock) Enable .....................................................................................................9030-03-10
Warning BDI (Lift Lock Out Percent) .............................................................................................9030-03-10
Battery-BDI Reset Volts ................................................................................................................ 9030-03-10
Battery- BDI Full Volts ...................................................................................................................9030-03-10
Battery-BDI Empty Volts ............................................................................................................... 9030-03-10
Battery-BDI Discharge Time ......................................................................................................... 9030-03-10
Battery-BDI Reset Percent ............................................................................................................9030-03-11
Undervoltage Cutback Range .......................................................................................................9030-03-11
User Undervoltage ........................................................................................................................ 9030-03-11
Total Maintenance Enable .............................................................................................................9030-03-11
Traction Maintenance Enable ....................................................................................................... 9030-03-11
Pump Maintenance Enable ...........................................................................................................9030-03-11
Maintenance Interval .....................................................................................................................9030-03-11
Reset Total Maintenance .............................................................................................................. 9030-03-11
Reset Traction Maintenance ......................................................................................................... 9030-03-11
Reset Pump Maintenance .............................................................................................................9030-03-11
Status Codes and Descriptions ............................................................................................................ 9030-03-12
Status Codes .................................................................................................................................... 9030-03-12
Status Code Descriptions ................................................................................................................. 9030-03-12
Group 20 Diagnostic Trouble Codes
DTC XX099 - Internal Fault............................................................................................................. 9030-20-1
DTC 30001 - LiftCoil........................................................................................................................ 9030-20-2
DTC 30003 - LwrCoil....................................................................................................................... 9030-20-4
DTC 30033 - Main Cont...................................................................................................................9030-20-6
DTC 30035 - Brake..........................................................................................................................9030-20-9
DTC 30037 - AlrmCoil....................................................................................................................9030-20-13
DTC 30039 - Audible Alarm (Opt)..................................................................................................9030-20-15
DTC 30060 - Mtr Curr.................................................................................................................... 9030-20-17
DTC 30061 - Mtr Open ................................................................................................................. 9030-20-17
DTC 30062 - Encoder....................................................................................................................9030-20-19
DTC 30067 - MainCont (Stuck Closed)......................................................................................... 9030-20-21
DTC 30068 - MainCont (Stuck Open)............................................................................................9030-20-25
DTC 30069 - Precharge.................................................................................................................9030-20-29
DTC 30080 30082 30083 - OverHeat............................................................................................9030-20-31
DTC 30086 - LowBatt.................................................................................................................... 9030-20-33
DTC 30087 - OverVolt................................................................................................................... 9030-20-35
DTC 30090 - 12 Vdc / 5 Vdc Supply Output.................................................................................. 9030-20-37
DTC 30106 - CANcomm................................................................................................................9030-20-40
DTC 30201 - Start Up.................................................................................................................... 9030-20-43
DTC 60211 - Start Up.................................................................................................................... 9030-20-43
DTC 30227 - Stalled ..................................................................................................................... 9030-20-48
DTC 30232 - Software .................................................................................................................. 9030-20-51
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TABLE OF CONTENTS
DTC 30247 - Parameter................................................................................................................ 9030-20-52
DTC 30248 - Low Temp.................................................................................................................9030-20-53
DTC 60050 - EmerRevr................................................................................................................. 9030-20-55
DTC 60210 - EmerRevr................................................................................................................. 9030-20-55
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9030-4

Group 03
General Maintenance and Diagnostic Data
General Troubleshooting
GENERAL TROUBLESHOOTING
In the event the lift truck does not operate correctly, a
status code is displayed on the display panel. Once
the status code is obtained, follow the procedures
outlined in this manual only after reviewing the
following information regarding the truck’s unique
electrical system and troubleshooting procedures.
NOTE: Due to the interaction of the traction controller
with all truck functions, almost any status code or con-
troller fault could be caused by an internal failure of the
traction controller. After all other status code proce-
dures have been followed and no problem is found,
the traction controller should be tested and replaced
as the last option to correct the problem.
Prior to troubleshooting systems and components on
the vehicle, ensure the battery voltage is correct and
within specifications. Make sure the battery connector
contacts are clean of corrosion and the battery polarity
within the connector is correct. Inspect that all fuses
are correct and are not the cause of component
failure. Ensure the key switch is in the ON position
when conducting voltage checks or verifying the
operation of a component. Make sure the brake switch
is functioning properly and is closed.
Many faults noted by lift truck’s electrical system may
be the result of loose wiring connections and/or broken
or shorted wiring within the lift truck. Begin the
troubleshooting process by carefully inspecting the
wiring involving the device or devices noted by the
onboard diagnostic system. .
The controllers are sealed units with no serviceable
components. Troubleshooting is usually limited to
accessing status codes and following the diagnostic
procedure provided for each status code.
Use standard testing procedures to verify inputs and
outputs when necessary.
CAUTION
Never attempt to probe through the back of the
connector plugs of the motor controller. These
plugs are special sealed plugs. Probing through
the back of the plugs will destroy the seal and can
cause a short circuit. If a circuit must be tested for
voltage, check for voltage at an amp-type plug, a
switch, or component. If a circuit is suspect, check
the circuit for continuity by disconnecting the plug
and testing continuity from the front (pin end) of
the plug.
Standard probes are too large to be inserted into
the center of female pins (sockets) of the special
sealed plugs and can damage or expand the pins.
Expanded pins will not provide good connections
once the plug is reconnected. The connectors are
shaped to allow the insertion of a small flat-blade
screwdriver into the connector. After inserting the
screwdriver into the connector, attach probes with
alligator clips to the shank of the screwdriver to
obtain readings.
Refer to 8000YRM 1512 for wiring diagrams and
additional circuit information.
DISCHARGING THE CAPACITORS
When working with the electrical systems of the truck,
it is necessary to discharge the internal or external
capacitors of the controllers associated with each
circuit affected.
ELECTRICAL SYSTEM General Maintenance and Diagnostic Data
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WARNING
DO NOT make repairs or adjustments unless you
have been properly trained and authorized to do
so. Improper repairs and adjustments can create
dangerous operating conditions. DO NOT operate
a lift truck that needs repairs. Report the need for
repairs to your supervisor immediately. If repair is
necessary, attach a DO NOT OPERATE tag to the
control handle and disconnect the battery.
Disconnect the battery and discharge the internal
or external capacitors before opening any com-
partment covers or inspecting or repairing the
electrical system. DO NOT place tools on top of
the battery. If a tool causes a short circuit, the high
current flow from the battery can cause personal
injury or property damage.
Some checks and adjustments are performed with
the battery connected. DO NOT connect the bat-
tery until the procedure instructs you to do so.
Never wear jewelry or other metallic items on your
fingers, arms, or neck when working near electri-
cal components. Metal items can accidentally
make an electrical connection and cause injury.
Before performing any tests or adjustments, block
the lift truck to prevent unexpected movement.
The capacitors in the transistor controllers can
hold an electrical charge after the battery is dis-
connected. To prevent an electrical shock and per-
sonal injury, discharge the internal or external ca-
pacitors before inspecting or repairing any compo-
nent in the electrical compartments. Make certain
that the battery has been disconnected.
DO NOT short across the motor controller termi-
nals with a screwdriver or jumper wire.
CAUTION
To avoid controller damage, always disconnect the
battery, discharge the internal or external capaci-
tors, and never put power to the controller while
any power wires are disconnected. Never short
any controller terminal or motor terminal to the
battery. Make sure to use proper procedure when
servicing the controller.
1. Move the lift truck to a safe, level area and
completely lower the forks. Turn the key switch to
the OFF position and attach a DO NOT
OPERATE tag to the control handle. Block the
drive wheel to prevent unexpected movement.
2. Disconnect the battery power cable connector
from the truck connector located on the top-left
side of the frame. Pull the battery cable connector
handle to separate the battery connector from the
truck connector.
3. Remove the operator compartment cover.
4. Discharge the internal or external capacitors in
the controllers by connecting a 200-ohm, 2-watt
resistor across the controller B(+) and B(-)
terminals of the combination controller. Remove
the resistor after discharging the capacitors. See
Figure 9030-03-1.
1. TRACTION CONTROLLER
2. POSITIVE CONNECTION
3. INSULATED JUMPER WIRES
4. 200-OHM, 2-WATT RESISTOR
5. NEGATIVE CONNECTION
Figure 9030-03-1. Discharging the Capacitors
General Maintenance and Diagnostic Data ELECTRICAL SYSTEM
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Electrical Test Equipment
ELECTRICAL TEST EQUIPMENT
Before beginning intrusive circuit checks, verify the
vehicle battery state of charge. Visually inspect
suspected connectors for loose, damaged, or corroded
terminals. Check for blown fuses and inspect circuits
for cause of overcurrent conditions. Physically check
mechanical operation to ensure a switch, relay, or
solenoid is not sticking or damaged.
NOTE: Measuring continuity between two terminals of
a switch while operating the switch will determine its
functionality.
PC Service Tool
The PC Service Tool is a Windows based service
application that is used to communicate with the
truck’s electrical control system. It can be used to
monitor the status and condition of various systems.
With this capability, the PC Service Tool can be used
to monitor component operation, or determine if
abnormal events have occurred in the truck, and assist
with diagnostics and troubleshooting.
Digital Multimeter (DMM)
Digital multimeters provide several measurement
functions in one tool. A DMM should be capable of
accurately measuring voltage, amperage, and
resistance. Ensure that the multimeter used in
troubleshooting procedures is accurate and that the
test leads do not have excessive resistance. A faulty
meter or damaged test leads will cause inaccurate
readings and incorrect electrical diagnoses.
Jumper Wires, Test Leads, and Test Lights
When using jumper wires, test leads, and test lights,
take care not to force tips into connector sockets. Use
appropriate clips and adapters to prevent damage to
connectors. Expanded or damaged sockets can cause
poor continuity between connections.
Jumper wires allow testing across a suspected open in
the circuit. Jumper wires can be used for located
opens, shorts, and performing voltage drops. If a
circuit operates correctly with the jumper wire in place,
and is faulty when the jumper wire is removed, a fault
can be found in the bypassed location.
Jumper wires can also be used to eliminate sections of
the circuit to diagnose either power or grounds. Using
the jumper wire to provide a component a known good
ground can help reduce the amount of checks needed
to diagnose a circuit.
Jumper wires can be used to bypass components
such as switches. If a faulty switch is suspected,
removing it from the circuit with a jumper wire can
determine if a switch or component is at fault.
Jumper wires can be used to check for open or faulty
relay contacts which are often sealed and can take
additional steps to properly diagnose.
Test lights can be used when quick voltage or ground
checks are necessary. Many features operate on
switched voltage, and using a test light as a load
device may be helpful. The test light may also be used
to verify continuity to B-. Discretion should be used
when troubleshooting a circuit using a test light, as the
light may illuminate even though there may be an
excessive amount of resistance on the ground circuit
or when a low voltage or amperage situation exists.
Basic Electrical Troubleshooting
ELECTRICAL CHECKS
The following electrical checks are used to diagnose
circuit and component faults on trucks. Review the
following information so that it may be applied when
diagnosing a fault or status code.
Voltage Checks
Voltage is electrical pressure or force that pushes
current through a circuit. The force is measured in
volts.
Low voltage to a load device will cause the device to
be inoperative or operate poorly. This can be caused
by a low battery source, high circuit resistance, poor
connections, or an open circuit; the resistance of poor
ELECTRICAL SYSTEM General Maintenance and Diagnostic Data
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connections or poor ground acts as an additional load
in the circuit, causing low voltage pushing current, or
amperage, through a device.
A voltmeter is used to perform:
•Measurement of force
•Presence of voltage
•Voltage drops
When using a voltmeter to determine if voltage is
present and capable of operating a device, connect
the positive meter lead to the power circuit of a
device’s connector and connect the negative meter
lead to the negative battery terminal.
Measuring the voltage drop is performed by
connecting the positive test lead to the positive side of
the device while simultaneously connecting the
negative meter lead to the negative side of the device.
The test can also be performed across a section of
wire that is faulty and suspected of having excessive
resistance. A voltage drop must be performed while
the device is operating. In a circuit with a single load
device, the device will drop the total voltage of the
circuit. If the device drops less than battery voltage, it
can be assumed that the circuits are using the
remaining voltage as a source of excessive resistance
or a poor connection exists, assuming the battery
state-of-charge is correct.
1. Verify battery connectors for loose terminals and
appropriate crimping. Measure voltage between
terminal before FU1 and B(-).
NOTE: Key in ON position.
Is voltage 24 ± 2.5 Vdc?
YES- Proceed to Step 3.
NO- Disconnect battery and proceed to Step 2.
2. Measure resistance between truck frame and
each of the following test points:
•Battery postivie wire after FU1
•B(+) and B(-)
•U-Phase cable
•V-Phase cable
•W-Phase cable
•Pump positive cable
•Pump negative cable
Is resistance ≥1M ohm?
YES- Charge battery, perform battery maintenance, for
non-maintenance free batteries, read battery Specific
Gravity level to be within manufacturer specification.
NO- Inspect for all cable insualtion throughout the
truck. Inspect battery corrosion around terminals for
proper crimping.
3. Measure battery voltage between terminal after
FU1 and B(-).
NOTE: Key in ON position.
Is voltage 24 ± 2.5 Vdc?
YES- Proceed to Step 5.
NO-Proceed to Step 4.
4. Measure continuity of Fuse FU1.
Is resistance <1 ohm?
YES- Proceed to Step 5.
NO- Replace Fuse FU1.
5. Ensure battery disconnect switch in UP position,
measure voltage between TS04 and B(-).
Is voltage same as battery voltage?
YES- Proceed to Step 6.
NO- Verify TS04 and TS05 terminal connections.
Refer to ELECTRICAL SYSTEM 2200YRM1508
for battery disconnect switch checks.
6. Measure continuity of Fuse FU2.
Is resistance <1 ohm?
YES- Proceed to Step 7.
NO- Replace Fuse FU2.
7. Measure resistance between key switch terminals
TS04 and TS05.
Is resistance <1 ohm?
YES- Inspect CPS 01 socket 1 for appropriate
crimping in terminals. Inspect voltage between
CPS01 socket 1 and B(-) to be same as battery
voltage. If not, inspect circuit 010 for excessive
resistance, damage, loose, or open connections.
NO- Inspect key switch terminals to be
appropriately connected. If connections are clean
and secure and resistance is ≥1 ohm, replace key
switch.
General Maintenance and Diagnostic Data ELECTRICAL SYSTEM
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Amperage Checks
An ammeter is used to measure amperage or current
flow through a circuit. An ampere is the measurement
of electron flow, which can be used to measure the
amount of electrons that are flowing through a circuit.
Ohm’s Law states that current flow in a circuit is equal
to the circuit voltage divided by total circuit resistance,
known as the potential difference. Since amperage is
the current in the circuit, increasing voltage also
increases the current, or amperage levels.
Measuring amperage is always performed by placing
the ammeter in series with the device or circuit. This
will cause all current to flow through the protected
meter. The circuit must be operating in order to
measure amperage. Never measure amperage on
high amperage circuits or in parallel to a circuit, this
can result in the damage of the meter and the
electrical system.
Resistance Checks
The ohmmeter is used to measure a circuit or device's
resistance in ohms. Ohmmeters use low internal
voltage and current which flow through an isolated
circuit or device being tested. The voltage of the meter
battery and the amount of current flow in the circuit are
used to calculate the circuit’s resistance. It is
necessary to disconnect or isolate the circuit being test
so not to damage the vehicle’s electrical system or the
ohmmeter.
An ohmmeter is used to perform:
•Resistance of a load device
•Resistance of conductors
•Value of resistors
•Operation of variable resistors
•CANbus termination resistors
•Continuity
Contactor and Contactor Coil Checks
1. Measure voltage between the coil's positive
terminal and B(-).
NOTE: Key in ON position.
Is voltage same as truck's battery voltage?
YES- Proceed to Step 2.
NO- Inspect the Coil's battery B(+) input circuit for
open or short.
2. Disconnect coil's ground control circuit. Measure
resistance between ground circuit terminal and
B(-).
NOTE: Actuate coil ground control to determine if
controller is sending activation signal to coil.
Is resistance <1 ohm?
YES- Proceed to Step 3.
NO- Inspect ground control circuit. Verify that controller
is receiving device input signal.
3. Measure battery voltage between main
contactor's battery B(+) terminal and B(-).
NOTE: Key in ON position.
Is voltage same as truck's battery voltage?
YES- Repair or replace faulty contactor.
NO- Inspect main contactor battery cable for loose,
damaged, or corroded connections.
Lift and Lower Switch Check
1. Operate lift/lower switch.
Does status code display if truck does not
respond to lift and lower command?
YES- Proceed to status code description section
within this manual to address the status code.
NO- Inspect lift and lower switches at tiller head.
Lower Function Fault
If the lower function is inoperative and no code has
been displayed, perform the following troubleshooting
procedures:
1. Open tiller head assembly and inspect tiller card.
Are lower switches connected to tiller card
connectors JP12 and JP15?
YES- Proceed to Step 2.
NO- Connect switches.
2. Disconnect JP12 and connect meter probes at
switch connector sockets (blue and black leads)
and operate switch.
Is resistance <1 ohm?
YES- Proceed to Step 3.
NO- Replace faulty switch.
ELECTRICAL SYSTEM General Maintenance and Diagnostic Data
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3. Measure resistance of tiller card switch JP12, pin
1 and pin 3.
Is resistance 2.7K ohms ± 0.27K ohms
YES- Proceed to Step 4.
NO- Replace faulty switch.
4. Measure resistance of tiller card switch JP15, pin
1 and pin 2.
Is resistance 1.4K ohms ± 0.14K ohms
YES- Suspect faulty tiller card.
NO- Replace faulty switch.
Lift Function Fault
If the lift function is inoperative and no code has been
displayed, perform the following troubleshooting
procedures:
1. Open tiller head assembly and inspect tiller card.
Are lower switches connected to tiller card
connectors JP10 and JP14?
YES- Proceed to Step 2.
NO- Connect switches.
2. Disconnect JP10 and connect meter probes at
switch connector sockets (blue and black leads)
and operate switch.
Is resistance <1 ohm?
YES- Proceed to Step 3.
NO- Replace faulty switch.
3. Measure resistance of tiller card switch JP10, pin
1 and pin 3.
Is resistance 2.7K ohms ± 0.27K ohms
YES- Proceed to Step 4
NO- Replace faulty switch.
4. Measure resistance of tiller card switch JP14, pin
1 and pin 2.
Is resistance 1.4K ohms ± 0.14K ohms
YES- Suspect faulty tiller card.
NO- Replace faulty switch.
Multiplexing
MULTIPLEXING AND THE CANBUS
Controller Area Network (CAN) Bus communication
allows multiple modules to communicate with each
other using the same digital data on a shared network,
this method of communication is known as
multiplexing. The CANbus is a pair of twisted insulated
wires that interconnect all the modules on the network.
The data transmitted is a digital encoded format.
Digital means only two states are used to transmit
data, High/On and Low/Off. This eliminates the need
for each module to be hard wired to each sensor.
Using Multiplexing, sensor information that may be
received by one module, can then be shared with all
other modules. The information is sent out over the
CANbus in an encoded form and any other module
that requires the information can pick it out from the
data stream.
The CANbus has two termination resistors (120 ohms)
that are connected in parallel. When resistance checks
are performed, a normal operating system will display
60 ohms between the CAN LO and CAN HI circuits.
The first 120 ohm termination resistor is located inside
the Tiller Control Card. To diagnose, proceed to
Troubleshooting the Tiller Control Card Termination
Resistor.
The second 120 ohm termination resistor is located in
the Traction Controller. To diagnose, proceed to
Troubleshooting the Traction Controller Termination
Resistor.
Troubleshooting the CANbus
NOTE: Refer to the latest Diagram YRM for the most
current circuit information.
When the CANbus is active and modules are
communicating, CAN HI and CAN LO voltage will be
approximately 5 volts when added together. If both
CAN HI and CAN LO have consistent 2.5 volt, there is
no communication on the CANbus.
If CAN HI is shorted to B(-) or CAN LO is shorted to
battery voltage, network communication will stop.
If you measure battery voltage on the data link, there
is a short to power in the circuit.
If you measure 0 volts while the CANBus is active,
there is a short to B(-) or an open in the circuit.
General Maintenance and Diagnostic Data ELECTRICAL SYSTEM
Check the Service Manual section in Yale Axcess Online for possible updates and check pertinent Bulletins
9030-03-6 Confidential/Proprietary - Do Not Copy or Duplicate

Internal control module failures can stop the entire
network from communicating. If there are no harness
problems, disconnect control modules one at a time
until CANbus communication returns.
With both 120 ohm termination resistors connected to
the CANbus, resistance between the two circuits
should read 60 ohms.
If CANbus resistance is 120 ohms, there is an open
circuit or a termination resistor is missing.
If resistance is 0 ohms, the two circuits are shorted
together.
1. Measure voltage between the diagnostic
connector, socket A and B(-).
NOTE: Key in ON position.
Is voltage approximately 2.5 volts?
YES- Proceed to Step 2.
NO- Inspect CAN HI circuit for open or short; if
voltage is 0 volts, the CAN HI circuit is shorted to
B(-) or open. If voltage is above 5 volts, the CAN
HI is shorted to power.
2. Measure voltage between the diagnostic
connector, socket B and B(-).
NOTE: Key in ON position.
Is voltage approximately 2.5 volts?
YES- Disconnect the battery and proceed Step 3.
NO- Inspect the CAN LO circuit for open or short;
If voltage is 0 volts, the CAN LO circuit is shorted
to B(-) or open. If voltage is above 5 volts, the
CAN LO is shorted to power.
3. Measure resistance between the diagnostic
connector, socket A and socket B.
Is resistance 60 ± 6 ohms?
YES- CANbus communication is operating
correctly.
NO- If resistance is 120 ohms; the CANbus has
an open circuit, missing, or damaged termination
resistor. If resistance is 0 ohms, the CANbus
circuits are shorted together. If resistance is open;
the CAN HI and/or CAN LO connection to the
diagnostic port may be open. Use the wiring
diagrams to detect and correct open circuit.
Troubleshooting the Tiller Control Card
Termination Resistor
Disconnect all Tiller Control Card connectors and
components.
1. Measure resistance between the Tiller Control
Card connector CJ2, pin 1 and pin 2.
Is resistance 120 ± 12 ohms?
YES- Reconnect the Tiller Control Card
connectors, components, and proceed to
Troubleshooting the Traction Controller
Termination Resistor.
NO- Replace Tiller Control Card.
Troubleshooting the Traction Controller
Termination Resistor
Disconnect all Traction Controller connectors, cables,
and components.
1. Measure resistance between the Traction
Controller connector CPS01, pin 21 and pin 34.
Is resistance 120 ± 12 ohms?
YES- Reconnect the Traction Controller
connectors, cables, components, and proceed to
Troubleshooting the CANbus.
NO- Replace Traction Controller.
User Interface
USER INTERFACE, SETUP, AND
TROUBLESHOOTING
The dash display has a LCD screen for displaying
truck system information. The dash display also
contains a battery state-of-charge indicator.
Status Code Indication
This feature indicates if a status code is available. If a
status code is present, the fault code number followed
by the status code description will be displayed. If
other status codes are present, it will display the
subsequent status code and description. Two seconds
will lapse between display screens before displaying
the code sequencing.
PARAMETERS
Utilize the User Interface to access and adjust
parameters. Not all parameters will be available and
will vary between truck applications.
ELECTRICAL SYSTEM General Maintenance and Diagnostic Data
Check the Service Manual section in Yale Axcess Online for possible updates and check pertinent Bulletins
Confidential/Proprietary - Do Not Copy or Duplicate 9030-03-7

Speed Steering Reduction
This optional parameter defines the speed reduction
that the motor will target from its current level once the
speed reduction sensor changes from ON to OFF. If
parameter is set at 75%, and the truck was been
driven at 1000 RPM, upon steering the motor will
decelerate to 750 RPM.
Traction Steering Decel Ramp
This optional parameter will determine the time that it
will take the motor to decelerate from current speed to
speed determined by Speed Steering Reduction
parameter. Larger values represent slower response.
Response-Full Accel Rate HS
This parameter will set the rate (in seconds) at which
the speed command increases when full throttle is
applied at high vehicle speeds. Larger values
represent slower response. See Figure 9030-03-2 for
relationship between Full Accel Rate HS, Full Accel
Rate LS, and Low Accel Rate.
NOTE: IN THIS EXAMPLE, HS = 70%, LS = 30%, TYPICAL MAX SPEED = 5000 RPM
Figure 9030-03-2. Acceleration Response Rate Diagram
Response-Full Accel Rate LS
This parameter sets the rate (in seconds) at which the
speed command increases when full throttle is applied
at low vehicle speeds.
Response-Low Accel Rate
This parameter sets the rate (in seconds) at which the
speed command increases when a small amount of
throttle is applied. This rate is typically adjusted to
affect low speed maneuverability.
Response-Neutral Decel Rate HS
This parameter sets the rate (in seconds) that is used
to slow down the vehicle when the throttle is released
to neutral at high vehicle speeds.
Response-Neutral Decel Rate LS
This parameter sets the rate (in seconds) that is used
to slow down the vehicle when the throttle is released
to neutral at slow vehicle speeds.
Fine Tuning-Partial Decel Rate
This parameter sets the rate (in seconds) that is used
to slow down the vehicle when the throttle is reduced
without being released to neutral. Larger values
represent slower response.
Fine Tuning-HS (High Speed)
This parameter sets the percentage of the Typical Max
Speed above which the “HS” parameters will be used.
General Maintenance and Diagnostic Data ELECTRICAL SYSTEM
Check the Service Manual section in Yale Axcess Online for possible updates and check pertinent Bulletins
9030-03-8 Confidential/Proprietary - Do Not Copy or Duplicate

Fine Tuning-LS (Low Speed)
This parameter sets the percentage of the Typical Max
Speed below which the “LS” parameters will be used.
Fine Tuning-Reversal Soften
This parameter, when set to larger values create a
softer reversal from regen braking to drive when near
zero speed. The parameter will soften the transition
when the regen and drive current limits are set to
different values.
Fine Tuning-Max Speed Accel
In some applications, the Max Speed value is changed
frequently over the CANbus. The Max Speed Accel
parameter controls the rate at which the maximum
speed setpoint is allowed to change when the value of
Max Speed is raised. The rate set by this parameter is
the time to ramp from 0 RPM to Typical Max Speed
RPM. If Max Speed is raised from 1000 RPM to 3000
RPM, the Typical Max Speed is 3200 RPM and the
rate is 10.0 seconds, it will take 10.0 * (3000–1000) /
3200 = 6.25 seconds to ramp from 1000 RPM to 3000
RPM.
Fine Tuning-Max Speed Decel
This parameter is like the Max Speed Accel parameter,
except that it controls the rate at which the maximum
speed setpoint is allowed to change when the value of
Max Speed is lowered. If one changes Max Speed
from 300 RPM to 1500 RPM, the Typical Max Speed is
3200 RPM, and the rate is 5.0 seconds, it will take 5.0
* (3000–1500) / 3200 = 2.34 seconds to ramp from
3000 RPM to 1500 RPM.
Interlock Timeout
This parameter will set the time for which the truck can
remain at idle condition while the arm is in operational
region B. See Figure 9030-03-3.
Mode (1 through 3) -Max Speed
This parameter defines the maximum requested motor
rpm at full throttle.
RPM = VDesired * 936
Example: RPM = 2.5MPH * 936 = 2340 rpm
Mode (1 through 3) -Max Accel
This parameter sets the rate (in seconds) at which the
motor speed command increases when throttle is
applied. Larger values represent slower response.
Mode (1 through 3) -Walk Accel
This parameter sets the rate (in seconds) at which the
motor speed command increases when throttle is
applied, when truck is not in turtle mode. Larger values
represent slower response.
Mode (1 through 3) -Max Decel
This parameter sets the rate (in seconds) that is used
to slow down the vehicle when the throttle is reduced.
Larger values represent slower response.
Mode (1 through 3) -Neutral Braking
This parameter adjusts how neutral braking occurs
progressively when the throttle is reduced toward the
neutral position or when no direction is selected.
Mode (1 through 3) -Max Braking
This parameter sets the rate (in seconds) at which the
vehicle slows down when full brake is applied or when
throttle is applied in the opposite direction.
Max Speed TM2
This parameter defines the maximum requested motor
rpm at full throttle when the truck is driven in Advance
Turtle mode in region B. See Figure 9030-03-3.
Max Accel TM2
This parameter sets the rate (in seconds) at which the
motor speed command increases when throttle is
applied. This parameter is applicable only while the
truck is driven while in Advance Turtle Mode. Larger
values represent slower response.
Max Decel TM2
This parameter sets the rate (in seconds) that is used
to slow down the vehicle when the throttle is reduced.
Larger values represent slower response.
Neutral Braking TM2
Neutral braking occurs progressively when the throttle
is reduced toward the neutral position or when no
direction is selected. This This parameter is applicable
only while the truck is driven while in Advance Turtle
Mode.
Max Braking TM2
This parameter sets the rate (in seconds) at which the
vehicle slows down when full brake is applied or when
throttle is applied in the opposite direction. This
parameter is applicable only while the truck is driven
while in Advance Turtle Mode.
ELECTRICAL SYSTEM General Maintenance and Diagnostic Data
Check the Service Manual section in Yale Axcess Online for possible updates and check pertinent Bulletins
Confidential/Proprietary - Do Not Copy or Duplicate 9030-03-9

Turtle Alarm enable
This parameter sets an alarm to indicate when the
truck has transition from turtle mode (TM1) to turtle
mode 2 (TM2). The truck will transition from TM1 to
TM2 when the truck is been driven in TM1 and turtle
button is depressed while tiller arm transition from
operational region A to operational region B. See
Figure 9030-03-3.
A. OPERATIONAL REGION A
B. OPERATIONAL REGION B
C. OPERATIONAL REGION C
Figure 9030-03-3. Operational Regions
Quick Lift Window
This optional parameter defines the minimum amount
of time that the lift button needs to be depressed to
activate Quick Lift.
Initial Lift Interval
This optional parameter sets the period of time for
which the truck will lift upon Quick Lift command. It
shall be enough to lift up the load from the ground so
that load wheels can move freely.
Full Lift Interval
This optional parameter sets the period of time for
which the truck will lift once traction is commanded
while Quick Lift mode.
Lift Run Time
This parameter sets the maximum allowable time to
have the motor pump running upon lift command.
BDI Warning (Lift Lock) Enable
This parameter enables the truck to lock the lift
function when BDI reaches a given percent
Warning BDI (Lift Lock Out Percent)
This parameter will set the battery discharge
percentage at which the truck will lock the lift function
Battery-BDI Reset Volts
The reset voltage level is checked only once, when
KSI is first turned on. Note that the BDI Reset Percent
parameter also influences the algorithm that
determines whether BDI Percentage is reset to 100%.
Reset Volts Per Cell should always be set higher than
Full Volts Per Cell.
Battery- BDI Full Volts
The full voltage level sets the Keyswitch Voltage that is
considered to be state-of-charge; when a loaded
battery drops below this voltage, it begins to lose
charge. The BDI (battery discharge indicator)
algorithm continuously calculates the battery state-of-
charge whenever KSI is on.
Battery-BDI Empty Volts
The empty voltage level sets the Keyswitch_Voltage
that is considered to 0% state-of-charge when the
truck is been used (loaded conditions). The BDI
(battery discharge indicator) algorithm continuously
calculates the battery state-of-charge whenever KSI is
on.
Battery-BDI Discharge Time
This parameter has two functions:
•Sets the minimum time for the BDI to count
down from 100% to 0%. If upon verification
battery voltage is below corresponding BDI
percent, BDI percent will decrement by one
percentage point.
•Sets the frequency at which the BDI will check
the battery voltage. If upon verification battery
voltage is below corresponding BDI percent,
BDI percent will decrement by one percentage
point.
General Maintenance and Diagnostic Data ELECTRICAL SYSTEM
Check the Service Manual section in Yale Axcess Online for possible updates and check pertinent Bulletins
9030-03-10 Confidential/Proprietary - Do Not Copy or Duplicate