GMG 3394-RT User manual

SERVICE PACK
3394-RT
6094-RT
3394-RT serial # 2339401000 - Current
6094-RT serial # 2609401000 - Current
November 2019
XXXXX

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Revision History
Date Update Reason

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Specications
Power
Power source Kubota Diesel Engine
Fuel tank capacity 25 gal / 95.0 L
Hydraulic system capacity 40 gal / 115.0 L
Weight
Standard 16,450 lbs
7462 kg
20,450 lbs
9276 kg
MODELS 3394-RT 6094-RT
Measurements
Working height maximum 39’ (11.9 m) 66’ (20.1 m)
Platform height maximum 33’ (10 m) 60’ (18.8 m)
Platform height - stowed platform oor 6’7” (2.02 m) 6’7” (2.02 m)
Platform length - retracted
- extended
17’5” (5.23 m)
24’10” (7.55 m)
17’5” (5.23 m)
24’10” (7.55 m)
Platform width - outside 75” (1.9 m) 75” (1.9 m)
Toeboard height 6” (15 cm) 6” (15 cm)
Height - stowed
rails lowered
122” (3.09 m)
92” (2.33 m)
128” (3.25 m)
97” (2.46 m)
Length stowed 17’ 5” (5.23 m) 17’ 5” (5.23 m)
Width 94” (2.38 m) 94” (2.38 m)
Wheelbase 113” (2.87 m) 113” (2.87 m)
Ground clearance - center 15” (38 cm) 15” (38 cm)
Productivity
Maximum platform occupancy 5 4
Lifting capacity 2,755 lbs (1250 kg) 1,200 lbs (540 kg)
Extension deck capacity (each deck) 500 lbs (227 kg) 500 lbs (227 kg)
Drive height full height 35’ (10.6 m)
Gradeability - stowed 45%
Turning radius - inside
Turning radius - outside
80” / 2.03 m
17’3” / 5.18 m
82” / 2.08 m
16.8’ / 5.12 m
Raise speed
Lower speed
36 seconds
31 seconds
60 seconds
55 seconds
Controls fully proportional
Drive four wheel
Drive speed, stowed 4.5 mph (7.2 km/h)
Drive speed, elevated 0.25 mph (0.4 km/h)
Tires - rough terrain 33 x 12 in 84 x 30 cm

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Specications
3394-RT Tunnel Speeds & Angles Drive Speed Tilt Angles
3394-RT Tunnel Machine
SLOPE ANGLE OPERATION
20 (6m) Height:
Fore and Aft direction:
°8 Red light comes on, alarm sounds, Lift/Drive interrupted
Side and Side direction:
°6 Red light comes on, alarm sounds, Lift/Drive interrupted
33 (10m) Height:
Fore and Aft direction:
°4 Red light comes on, alarm sounds, Lift/Drive interrupted
Side and Side direction:
°4 Red light comes on, alarm sounds, Lift/Drive interrupted
13 (4m) Height:
Fore and Aft direction:
°9 Red light comes on, alarm sounds, Lift/Drive interrupted
Side and Side direction:
°8 Red light comes on, alarm sounds, Lift/Drive interrupted
26 (8m) Height:
Fore and Aft direction:
°5 Red light comes on, alarm sounds, Lift/Drive interrupted
Side and Side direction:
°5 Red light comes on, alarm sounds, Lift/Drive interrupted
Stowed Height 10 km/h
4m Height 5 km/h Up to 9°
6m Height 4 km/h Up to 8°
8m Height 3 km/h Up to 5°
10m Height 2 km/h Up to 4°

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Table of Contents
Introduction.......................................................................................................1
Section 1 - Introduction
Section 2 - Component Locations
Component Locations ........................................................................................2
Platform Controls ...............................................................................................3
Lower Controls ...................................................................................................5
Section 3 - Emergency Systems
Emergency Lowering .........................................................................................6
Section 4 - Maintenance
Maintenance ......................................................................................................7
Maintenance Lock .............................................................................................8
GP400 Menus on EZcal ....................................................................................9
Section 6 - Electrical Schematic Drawing
Schematic.......................................................................................................22
Section 7 - Hydraulic Schematic Drawing
Schematic .........................................................................................................24
Section 5- Troubleshooting
Top Level Menu Options .................................................................................10
Help Menu Options...........................................................................................10
Diagnostic / System Level Options.................................................................. 10
Diagnostic Menu Options:
Platform Level ................................................................................................11
Ground Level .................................................................................................11
Inputs Level ....................................................................................................11
Matrix Inputs Level ........................................................................................11
Outputs ..........................................................................................................12
GP400 Analogs .............................................................................................12
Matrix Analogs ...............................................................................................12
GP400 Monitors Submenu .............................................................................12
Matrix Outputs ...............................................................................................12
GP400 Diagnostics...........................................................................................12
GP400 LED Flash Codes ................................................................................. .20
GP400 Help Messages .....................................................................................15

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Page 1
Introduction
The Operator’s Manual must be read and understood prior to operating your GMG Aerial Work
Platform. The user/operator should not accept operating responsibility until he/she has read and
understands the operator’s manual as well as having operated the GMG Aerial Work Platform under
supervision of unauthorized, trained and qualied operator.
It is essential that the operator of the aerial work platform is not alone on the workplace during
operation.
Modications of this machine from the original design and specications without written permission
from GMG are strictly forbidden. A modication may compromise the safety of the machine, subjecting
operator(s) to serious injury or death.
1 - Introduction
This Service Pack has been designed to provide you, the technician with a quick reference to some of the most
used instructions and information which can be helpful to troubleshoot and service your GMG Aerial Work
Platform. This Service Pack is provided as a quick reference guide and does not include all safety information nor
all service detail found in a Service Manual. Please refer to all other provided documentation.
Your GMG Aerial Work Platform has been designed, built, and tested to provide safe, dependable service.
Only authorized, trained and qualified personnel should be allowed to operate or service the machine.
GMG, as manufacturer, has no direct control over machine application and operation. Proper safety
practices are the responsibility of the user and all operating personnel.
Preface
Copyright and Amendment
Text and illustrations herewith enclosed may not be or duplicated, not in full or in part or by any means.
Because of the possible time lag between the introduction of technical modifications (an on-going process,
the aim of which is to offer products which are being continually improved), the data contained in this
edition is liable to change at any time and is therefore not binding.
Global Machinery Group
Global Machinery Group, Inc.
3428 Bullock Lane
San Luis Obispo, CA 93401 USA
Phone: [phone]
www.goGMG.com
Your GMG Aerial Work Platform has been designed, built, and tested to provide safe, dependable service.
Only authorized, trained and qualified personnel shall be allowed to operate or service the machine. GMG,
as manufacturer, has no direct control over machine application and operation. Proper safety practices are
the responsibility of the owner, user and operator.
If there is a question on application and/or operation or service contact:
Global Machinery Group, Inc.

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Page 2
Component Locations
General Locations
Module Component Locations
Deck Extension
Main Platform Deck
Lift Cylinders
Beams
Chassis
Lower Controls
Module
Engine
Compartment
Outrigger
Fuel/ Hydraulic
Fluid Module
Platform Controls Deck Extension
Release Handle
Fuel Sight Gauge
Hydraulic Fluid Sight Gauge
Hydraulic Tank
Fuel Tank
Fuel/Fluid
Module
Hydraulic
Valve Blocks
Battery
GP400 Base Controls
Control
Module
Battery Disconnect
(inside)
2 - Component Locations

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22
23
Platform Controls
F L
F L
R L
R L
R R
R R
F R
F R
AUTO
D
1
2
14
4
6
8
9
11
12 13
10
5
15
16
17
19
18
20
21
7
3
2- Component Locations

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Page 4
Control Description
1Emergency Stop Switch Push IN to stop all functions
Pull OUT to reset
2Lift / Drive Selector Switch Push to the LEFT to LIFT and to the RIGHT to DRIVE
3Horn Button Press and hold to sound warning horn
4Engine Start Switch Push UP to start engine
5Lights and Powered Accessory
Switch Push DOWN to power lights and UP to power accessories
6Engine Preheat Switch Push UP to preheat engine
7High / Low Torque Switch Push to the LEFT for engine high torque mode and to the RIGHT for high
speed mode
8High / Low Engine RPM Switch Push to the LEFT for engine low RPM
Push to the RIGHT for engine high RPM
9FL Outrigger Switch Push UP and hold to raise the LEFT front outrigger
10 FR Outrigger Swtich Push UP and hold to raise the RIGHT front outrigger
11 Auto Level Switch Push UP to auto level the machine and push DOWN to auto retract all 4
outriggers
12 RL Outrigger Switch Push UP and hold to raise the LEFT rear outrigger
13 RR Outrigger Switch Push UP and hold to raise the RIGHT rear outrigger
14 Joystick
Drive Controls Forward and Reverse travel
Lift
Move toward operator to ELEVATE platform. Lift speed
increases proportional to the Joystick movement.
Move away from operator to LOWER platform.
15 FL OR Indicator Light indicates that the left front outrigger is in operation
16 FR OR Indicator Light indicates that the right front outrigger is in operation
17 RR OR Indicator Light indicates that the left rear outrigger is in operation
18 RL OR Indicator Light indicates that the right rear outrigger is in operation
19 Tilt Indicator Light indicates the machine is over the allowed tilt angle
(alarm will also sound)
20 Overload Indicator Light indicates the machine has more than the max allowed weight on it
(alarm will also sound)
21 Elevated Height Indicator Light indicates that the machine is past the height designating the
machine as “elevated”
22 Steer Switch Push LEFT side of switch to steer LEFT
Push RIGHT side of switch to steer RIGHT
23 Function Enable Switch Squeeze the top or bottom of the enable switch and hold to enable DRIVE,
LIFT, and STEER functions
2 - Component Locations

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ENTERESC
Control Description
1LED Display Onboard Diagnostics and Clock display
2Circuit Breaker Trips when there is excessive electrical load
Push to reset
3Hour Meter Indicates total elapsed time of machine operation
4Emergency Down Switch Push DOWN and hold to LOWER the platform
5Lower / Raise Switch Push UP and hold to RAISE platform
Push DOWN and hold to LOWER the platform
6Engine Start Switch Push UP and hold to start engine
Push DOWN and hold to preheat engine
7High / Low Engine RPM Switch Push to the LEFT for engine low RPM
Push to the RIGHT for engine high RPM
8Platform / Base Selector Switch Turn the Key to the LEFT to operate from the Platform
Turn the Key to the RIGHT to operate from the Base
9Emergency Stop Switch Push IN to stop all functions
Pull OUT to reset
1
2
8
9
3
4 5 6 7
Lower Controls
2 - Component Locations

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Emergency Systems
If the control system fails while the platform is elevated, have an experienced
operator use the emergency lowering procedure to safely lower the platform.
Do not attempt to climb down beam (scissors) assembly.
Emergency Lowering
The Emergency Lowering System is used to lower the platform in case of power or valve failure. To lower the
platform, activate the Emergency Lowering Switch.
The Emergency Lowering Switch is located on the base controls.
Emergency Lowering Switch
(Lower Control Panel)
3- Emergency Systems

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4- Maintenance
Maintenance
DO NOT operate this machine until you have read and understood the Safety section of the
Operators Manual, have performed the Jobsite Inspection, Pre-Start Inspection and Routine
Maintenance, and have completed all the test operations detailed in the Operating Instructions.
Tag and remove a damaged, malfunctioning or modified machine from service. DO NOT use a damaged,
malfunctioning or modified machine.
Always use the maintenance lock to block the scissor assembly in place before
servicing the machine with the platform elevated.
Hydraulic uid under pressure can penetrate and burn skin, damage eyes, and
may cause serious injury, blindness, and death. Repair leaks immediately.
Fluid leaks under pressure may not always be visible. Check for pin hole leaks
with a piece of cardboard, not your hand.
Immediately report any damage, defect, unauthorized modification or malfunc-
tion to your supervisor. Any defect must be repaired prior to continued use.
DO NOT use a damaged, modified or malfunctioning machine.
Never leave hydraulic components or hoses open. Plug all hoses and tting
immediately after disassembly to protect the system from outside
contamination (including rain). Never open a hydraulic system when there are
contaminants in the air. Always clean the surrounding area before opening
hydraulic systems.
Use only recommended lubricants. Improper lubricants or incompatible
lubricants may cause as much damage as no lubrication.
Watch for makeshift “xes” which can jeopardize safety as well as lead to
more costly repair.
Inspection and maintenance should be performed by qualied personnel
familiar with the equipment.

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4- Maintenance
Maintenance Lock
Maintenance Lock
Never perform service on the machine with the platform elevated without rst
blocking the scissor assembly using the maintenance lock.
Setting The Maintenance Lock
1. Elevate platform approximately 16 feet (5 m) and rotate maintenance lock to
Blocked position
2. Lower platform until scissor assembly comes to rest on the maintenance lock.
3. Scissor assembly is blocked.

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5- Troubleshooting
Never perform service on the machine with the platform elevated without rst
blocking the scissor assembly using the maintenance lock.
Should you experience erratic operation or notice any malfunction while
operating this machine, discontinue use immediately.
Call for assistance and report the incident to your supervisor, and do
not use the machine until it has been checked by a trained, qualied
mechanic.
Machine functions will not operate:
•Battery properly connected?
•Battery fully charged?
•Function toggle switch or the Enable Switch not activated?
•Selector Key Switch in proper position?
•Both Emergency Stop Switches reset?
•Hydraulic fluid level low?
•Obvious fluid leak or damaged component?
•Wires disconnected, broken, or loose?
•Motor control processor Diagnostic LED OFF. LED should be ON.
Troubleshooting
When the EZcal hand-held device is connected to the GP400 control module, a two line
display shows various menus and settings. At any time the top line of the display describes
the currently selected menu and the bottom line shows the currently selected item in that
menu.
Six buttons on EZcal allow easy navigation through the menus:
and  change the selected item (the bottom line display)
ENTER enters the selected new menu when available (top line display changes)
and  adjusts the selected item when available (at “ACCESS LEVEL” 1)
ESC exits the current menu back to the previous menu
IMPORTANT: Different GP400 configurations will have slightly different menus, with added
or omitted items – this document presents a general style and should be reviewed along
with customer specific documentation.
GP400 MENUS ON EZcal

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5- Troubleshooting
Top Level Menu Options
HELP
DIAGNOSTICS
ACCESS LEVEL
ADJUSTMENTS
SETUPS
CALIBRATIONS
Select this menu to see a description of current GP400 status Select
this menu to see switch & sensor input status & logged data
Select this menu & enter correct code to enable adjustments and
calibrations
Select this menu to see and adjust GP400 settings
Select this menu to carry out initial set-up of the GP400
This menu is intended for use by GP400 design engineers only!
SERIAL NUMBER Select this menu to view the serial number of the controller
Help Menu Options
(help message)
LOGGED HELP
A message displays current GP400 status, indicating if
everything is OK or if there is a reason for restricted functionality
Press ENTER when viewing the current HELP message to see a
log of recent HELP messages; press to  see older messages,
and  to see newer ones; press ESC to return to the current
HELP message
Diagnostics / System Level Options
MODE
MODE\INTERLOCK
SUPPLY
VALVESUPPLY
MOTOR V
MOTOR I
TEMPERATURE
TILT
TILTED
HEIGHT
LOAD
OVERLOADED
LAST MOVED
ELEVATED
Displays current operating mode or interlock
When current operating mode shows INTERLOCKED, press
ENTER to see the reason for the interlock; press ESC to return to
the current operating mode
Displays battery supply voltage
Displays valve supply
Displays motor voltage
Displays motor current
Displays temperature (°C)
Displays tilt values (X°, Y°)
Displays whether system is in tilted mode (measured tilt exceeds
tilt trip points)
Displays platform height, calculated from height sensor(s) and
data stored during calibration
If two EZfit sensors are installed, press ENTER when viewing the
HEIGHT (which is the average of the two sensors), to see the
individual measurements of the two sensors, named HEIGHT1
and HEIGHT2 (press è and ç to see both); press ESC to return
to the average HEIGHT
Displays platform load, estimated from lift cylinder pressure
measurement, platform height, and height/pressure curves stored
during calibration
Displays whether system is in overload mode (platform load
exceeds load trip point, at/above overload height)
Displays whether the most recent platform movement was UP or
DOWN; this is important if the lift cylinder pressure is affected by
the direction of movement (during calibration, separate
measurements are collected during lifting and lowering)
Displays whether system is in elevated mode

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5- Troubleshooting
DIAGNOSTICS / PLATFORM MENU OPTIONS
TRIGGER
DLD
JOYSTICK
FWD/UP
REV/DOWN
LEFT
RIGHT
POSITRAC
EMSp
Displays ON when platform trigger pressed
Displays drive / lift (deck) mode (from drive / lift switch)
Displays joystick position (%)
Displays ON when joystick is moved toward FWD or UP
Displays ON when joystick is moved toward REV or DOWN
Displays ON when steer left button pressed
Displays ON when steer right button pressed
Displays ON when traction switch is pressed
Displays ON, indicating platform EMS is active
DIAGNOSTICS / GROUND MENU OPTIONS
UP
DOWN
OUT
IN
EMSg
Displays ON when up switch pressed
Displays ON when down switch pressed
Displays ON when (optional) deck out switch pressed
Displays ON when (optional) deck in switch pressed
Displays ON, indicating ground EMS is active
DIAGNOSTICS / INPUTS MENU OPTIONS
P7-1
P7-2
P7-3
P7-4
Shows P7-1 input status (normally valve supply, ON always)
Shows P7-2 input status (normally EMS ground)
Shows P7-3 input status
Shows P7-4 input status (normally EMS platform)
Shows P14-1 input status
Shows P14-2 input status
Shows P14-3 input status
Shows P15-1 input status
Shows P15-2 input status
Shows P15-3 input status
…
P14-1
P14-2
P14-3
…
P15-1
P15-2
P15-3
…
DIAGNOSTICS / INPUTS / MATRIX INPUTS MENU OPTIONS
MP2-1
MP2-2
…
MP3-1/4
MP3-1/5
…
MP3-2/4
MP3-2/5
Shows MP2-1 input status from CANbus connected Platform
Matrix
Shows MP2-2 input status from CANbus connected Platform
Matrix
Shows MP3-1 to 4 input status from CANbus connected
Platform Matrix
Shows MP3-1 to 5 input status from CANbus connected
Platform Matrix
Shows MP3-2 to 4 input status from CANbus connected
Platform Matrix
Shows MP3-2 to 5 input status from CANbus connected
Platform Matrix

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5- Troubleshooting
DIAGNOSTICS / ANALOGS / GP400 ANALOGS MENU OPTIONS
P8-1
P8-2
Displays voltage measurement of P8-1 analog input
Displays voltage measurement of P8-2 analog input
…
DIAGNOSTICS / ANALOGS / MATRIX ANALOGS MENU OPTIONS
MP2-6
MP2-7
Displays voltage measurement of MP2-6 analog input from
CANbus connected Platform Matrix
Displays voltage measurement of MP2-7 analog input from
CANbus connected Platform Matrix
DIAGNOSTICS / OUTPUTS MENU OPTIONS
P4-1
P4-2
P4-3
P4-4
MONITORS
Displays state of P4-1 output
(press ENTER to see 0%-100% proportional output
state) Displays state of P4-2 output
Displays state of P4-3 output
Displays state of P4-4 output
(press ENTER to see 0%-100% proportional output state)
Select this sub-menu to view output monitors
DIAGNOSTICS / OUTPUTS / GP400 / MONITORS SUB-MENU OPTIONS
MAIN
SAFE
SAFETOP
Displays monitor of most GP400 outputs (except P4-
12/13/14/15 “safe” outputs)
Displays monitor of “safe” P4-12/13/14/15 outputs
Displays monitor of redundant “safe” pre-output
DIAGNOSTICS / OUTPUTS / MATRIX OUTPUTS MENU OPTIONS
MP4-1
MP4-2
Displays state of MP4-1 output of CANbus connected Platform
Matrix
Displays state of MP4-2 output of CANbus connected Platform
Matrix
GP400 DIAGNOSTICS
Diagnostics on the GP400 controllers are primarily accessible using the EZcal hand-held
device.
Menus available include DIAGNOSTICS which offers display of information relevant to the
operation of the controller. One most important diagnostic display is MODE which can be
found in the DIAGNOSTICS/SYSTEMS menu.
The purpose of MODE is to indicate the current state of the GP400 controller with a short
description:
INITIALIZING
Preparing to operate, immediately after power-on
SHUTDOWN!
All operation prevented – for example both the PLATFORM & GROUND EMS inputs
are active together

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5- Troubleshooting
CHECK CANbus
All operation prevented – CANbus communications is not successful (for example to
the platform matrix module, if applicable)
PLATFORM, GROUND
Ready to operate, from the platform or ground controls as indicated (selected by the
two EMS inputs)
GROUND UP, GROUND DOWN, GROUND OUT, GROUND IN
A ground function is operating normally
GROUND UP LOCKED, GROUND DOWN LOCKED, GROUND OUT LOCKED, GROUND
IN LOCKED
A ground function is selected but not allowed (for example, the switch was closed at
power-on)
GROUND FAULTY
Multiple ground function inputs are active at the same time
WAITING FOR TRIGGER
A platform function is selected, but the trigger switch is not closed (close trigger
switch to proceed)
TRIGGER CLOSED
The platform trigger switch is closed, but no function is selected (select a function to
proceed)
GP400 DIAGNOSTICS (continued)
TRIGGER LOCKED
The platform trigger switch was closed at power-on, or closed for too long with no
function selected (see SETUPS/INTERLOCKS/TRIGGERonly)
FORWARD, REVERSE
A platform drive function is operating normally
FORWARD (LEFT), FORWARD (RIGHT), REVERSE (LEFT), REVERSE (RIGHT)
A platform drive function is operating normally, with steer also active
STEER LEFT, STEER RIGHT
A platform steer function is operating normally (without drive)
UP, DOWN
A platform lift/lower function is operating normally
OUT, IN
A platform deck extend/retract function is operating normally
FORWARD LOCKED, REVERSE LOCKED
A platform drive function is selected but not allowed (for example, the switch was
closed at power-on)
LEFT LOCKED, RIGHT LOCKED
A platform steer function is selected but not allowed (for example, the switch was
closed at power-on)
UP LOCKED, DOWN LOCKED
A platform lift/lower function is selected but not allowed (for example, the switch was
closed at power-on)
OUT LOCKED, IN LOCKED
A platform deck function is selected but not allowed (for example, the switch was
closed at power-on)

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5- Troubleshooting
GP400 DIAGNOSTICS (continued)
CHECK DRIVE/LIFT
Neither platform drive nor platform lift select is active, or both are active at the same
time
CHECK JOYSTICK
Both platform joystick directions are active at the same time
STEER FAULTY
Both platform steer directions are active at the same time
INTERLOCKED
An interlock shutdown is active, preventing one or more functions. The interlock can
be due to many different causes – press <ENTER> from the EZcal MODE display to
see the precise cause of the interlock (listed below) – press <ESC> from that display
to return to the MODE display:
ARMGUARD
During descent, the EZlift 230 can be configured to stop movement and
provide an armguard delay (allowing time to check that everything is clear
before continuing descent)
Release and re-select DOWN to continue lowering (after the delay time has
passed)
If the armguard feature is not wanted, set ADJUSTMENTS/LIFT/
ARMGUARD/@HEIGHT to 101%
BATTERY
Battery voltage is too low (or high!) to allow movement
EXTERNAL ALL, EXTERNAL DRIVE, EXTERNAL LIFT
An external cutout input is preventing functions – determine the cause of the
external cutout
NO VALVE SUPPLY
Check power to P3-2
NONE
There is no interlock (the interlock has cleared while viewing the display)
OVERLOADED
The platform is overloaded, with the EZlift 230 configured to measure
overload and shut down functions when overloaded – reduce platform load
TEST MODE
The EZlift 230 test mode is active – switch power off and on again to clear
TILTED
The machine is tilted beyond limits, with the EZlift 230 configured to prevent
some functions when tilted (perhaps also elevated) – descend, then move
machine to a more level location
(see SETUPS/TILT SETUPS/TILT SHUTDOWN and ELEV.TILT
SHUTDOWN)
TOO HIGH
The platform is too high to allow some functions – descend first
(see ADJUSTMENTS/HEIGHTS/MAX DRIVE and MAX LIFT)

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5- Troubleshooting
GP400 DIAGNOSTICS (continued)
TOO HOT
The EZLIFT 230 heatsink has reached 75ºc, preventing all functions except
lowering. Functions will be allowed again when the heatsink cools to below
70ºc.
The heatsink temperature can be viewed in the DIAGNOSTICS/SYSTEM/
TEMPERATURE display.
Review the installation – the heatsink must be bolted to a significant metal
panel of the machine, capable of dissipating heat to the environment.
UNCALIBRATED
The height and/or pressure sensors have not been calibrated and are required
to measure platform height and/or load
If overload functions are active (ADJUSTMENTS/OVERLOAD TRIP@,
LAMP@ or ALARM@ set to a non-zero value) then both the height and
pressure sensors must be calibrated
If overload functions are not active, but height-based decisions are active
(ADJUSTMENTS/ HEIGHT values set to between 1% and 100%) then the
height sensors must be calibrated
Calibration procedures are accessible from the SETUPS/HEIGHT SETUPS
and SETUPS/LOAD SETUPS menus
GP400 HELP MESSAGES
In addition to the MODE displays detailed above, the GP400 provides a HELP message
display and associated flash code LED.
Various HELP messages can be displayed to indicate different conditions; some messages
also flash the LED on the controller so that even without access to an EZcal, some simple
diagnostics are possible.
IMPORTANT: It is strongly recommended not to rely on the LED flash codes, but to use an
EZcal – the HELP message and diagnostic displays provides a much higher detail of
information.
This section lists “information only” HELP messages – there is no LED flash code (the
LED remains on steady):
STARTUP! (no flash code)
The GP400 has just been powered on and is carrying out some initialization
steps prior to being ready to operate. If you select a function during this time, it
may be locked out until you release then re-select it
EVERYTHING OK (no flash code)
The GP400 is ready to operate in platform mode when a function is selected
NOTE: If this is the HELP message when a function is selected, check for open-
circuit switches or wiring
GROUND MODE ACTIVE! (no flash code)
The EZlift 230 is ready to operate in ground mode when a function is selected
DRIVING!
LIFTING!
LOWERING!
STEERING!
EXTENDING DECK!
(no flash code)
(no flash code)
(no flash code)
(no flash code)
(no flash code)