Ryobi RY48110 Operating instructions

Ryobi RY48110/11/12 Riding Tractor
Electrical Components Troubleshooting and Testing
(Lead-Acid Battery Version)
J.Davis 9-4-2018
1

Table of Contents
•WARNING
•Mower Overview
•A Word about Brushless Motors
•Using this Manual
•DMM and Other Tools
•Block Diagram and Control Flow
•Troubleshooting: General
•Troubleshooting: Detailed
•Component Locations
•Main Battery Connection
•Testing Main Fuse
•Testing Battery Voltage
•Separating Connectors
•Control Panel
•Testing PTO Switch
•Testing RMO Switch
•Testing F-N-R Switch
•Testing Cruise Switch
•Testing Fuel Gage / Hour Meter
•Testing Key Switch
•Testing USB Port
•Testing Headlight Switch
•Testing Headlight Assembly
•Testing Accelerator (angular transducer) 2
•Testing Brake Switch
•Testing Beeper
•Testing Seat Switch
•Testing Master Blade Motor Controller
•Testing Slave Blade Motor Controller
•Remove / Replace Drive Motor Controller
•Testing Drive Motor Controller
•Testing Master and Slave Motors
•Testing Drive Motor
•Testing Drive Motor Hall Sensors
•Testing 48V-12V Converter and fuse
•Replacing the 48V-12V Converter
•Testing Relay
•Testing Relay Diode
•Testing Charge port and interlock
•Testing the Battery Charger
•Testing the Temperature Sensor
•Charger Error Codes
•Wire Harness
•Pre and Post-Repair Checklist
•Electronic Tips for the Mechanical Small Engine Tech
•Electronics Terms, Symbols and Tools
•Using the Digital Multi-Meter (DMM)

C
THIS MATERIAL INTENDED ONLY FOR TECHNICIANS TRAINED IN ELECTRICITY.
Technicians should wear personal protective equipment, such as rubber
gloves and safety glasses
Dangerous voltages /currents are present. Exercise caution at all times
This manual assumes knowledge of basic electrical equipment such as DMM (Digital Multi Meter)
to measure voltage, current, resistance, continuity, and diodes.
3
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Mower Overview
The Ryobi riding tractor is completely electrical,
consisting of 3 brushless Motors and controllers
for each motor:
•A brushless electric motors/controllers for each
of the 2 blades
•1 brushless motor/controller to propel the
mower. This Drive motor controller also contains
the “brains” that responds to various inputs such
as the accelerator, seat switch, cruise control, etc.
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A word about Brushless Motors
Brushless motors operate quite differently than brushed
motors, which you may be used to (i.e. a starter motor)
With a brushed motor, you can quickly check them by
applying voltage to the two terminals.
Brushless motors can be recognized by 3terminals.
These 3 terminals require a controller to operate them
and to “fire” these 3 phases in a precise fashion similar to
spark plugs firing a 3 cylinder gas motor. Applying a
voltage directly to these phases may cause damage.
5
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Using this Document
•Anything in blue can be clicked on to jump directly to the page of that
topic. (This document is also printer-friendly, so you can have it in front of
you while servicing the mower.) If you print this document, we
recommend printing it in landscape mode and in color
•A block diagram shows the general flow to visualize how the mower is
connected and a chart shows general symptoms/solutions for repairs.
•Electronics tips , Terminology and using a Digital Multi-Meter (DMM) are
included for the technician familiar only with gas machines.
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Block Diagram And Control Flow
Batteries
Main
Fuse
Charge
Port/lockout/
battery temp
48V to 12V
(DC to DC)
converter Relay
Fuel
gage
Drive
Controller
Control Panel
Brake
Switch
Beep
Seat
switch
Fuse
Master
Blade
Control
Slave
Blade
Control
Motor Motor
Motor
Head
Lights
PTO
RMO
FNR
Cruz
Light
Gage
USB
Key
Switch
Accelerator
Note: A detailed wire harness diagram is
located later in this document
USB
Hall Sensors
Important: Master and slave have
A communication link. If one blade
Motor or controller fails, BOTH will
Shut down
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48V

Troubleshooting: General
•Follow the block diagram on the previous page
•Test the easiest components first
•Mower should be fully charged (if possible)
•Before disassembly:
–Attempt to charge mower (note any error LED indications)
–Check for voltage at charge port
–Check if USB indicator and headlights work (this tests DC
converter)
•Remove instrument panel cover
–Test key switch
–Check all other connections while panel is removed.
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Troubleshooting: Detailed
Use the block diagram as a guide
1. Verify the battery charger is functional by plugging it into the charge port on the back of the mower and let it charge.
2. If necessary, further test the charger and charge port. Replace as needed. Charge port, Interlock, and temp sensor should be replaced together.
3. Test the key switch by operating it, making sure it has a solid “click” when turned on or off. Replace if necessary
4. Test and replace main relay and diode as necessary. (Note: when you turn the mower on, you should hear the relay click)
5. If necessary, check the main fuse. If it is blown, check the system for signs of a short circuit before replacing the main fuse
6. If the fuel gage has power, but not display or malfunctions, replace the fuel gage
7. If ONLY the fuel gage works when the key is turned on, test/replace the 48-to-12V DC converter and 5A fuse as necessary
Note: this fuse is a common part available at any automotive store
8. If the mower will not drive:
a. Make sure the seat switch is functional and activated
b. Test the F-N-R switch. Replace if necessary
c. Test the accelerator transducer. Replace if necessary
d. Test the brake switch. Replace if necessary
e. If the mower still will not drive, test the Drive Motor controller. Replace if necessary
9. Test the blade operation by pulling up on the PTO switch
a. Make sure the seat switch is functional and activated
b. Test the master and slave motors. Replace as a pair if found bad
c. Test the master and slave controllers. Replace as a pair if found bad
d. If the mower blades still will not operate, replace the Drive motor controller (same as step 8e above)
10. If the mower works except for the headlights, test the headlight switch and headlights. Replace as necessary
a
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Digital Multi Meter (DMM)
Typical DMM (Fluke 87). Note the dial
is set to the “DIODE” function.
this function will be used in
many of the following procedures.
Also note where the red and black jacks
of the test leads are connected to the DMM.
If you are unfamiliar with a DMM, please read the section
Electronics Tips for the Mechanical Small Engine Technician
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Other Helpful Tools and Parts
11
12V output
5V output
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Component Locations
12
Headlights
Master/slave
Blade
controllers
Drive
Controller
Seat
Switch
Beeper
DC-DC
converter
(underside)
Brake Switch
Accelerator
transducer
Access panel
(under seat)
Charge port
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Main Battery Connection
The main battery disconnect is located directly under the seat
access cover. It may takes considerable pressure to separate the halves.
If you can not separate by hand, you may need a blunt instrument to push
in the hole in the direction indicated.
Note that one half of the connector is screwed to the frame and will not
move. Be careful not to damage the connector.
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Testing Main Fuse
1. Disconnect main battery connection
2. Open the plastic box to access
main fuse.
3. Set DMM to Resistance
Measure where indicated below.
Ensure the nuts are tight, but not
overtightened, as this can cause the fuse
to twist and break.
If fuse is blown, replace
only with the same physical
size and same Amperage.
14
IMPORTANT: If the main fuse is blown, find the source of problem before replacing fuse
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Testing Battery Voltage
1. Set DMM to “DC Volt” mode.
2. Turn mower on.
3. Pull PTO switch up (Power Take Off/Blade Engage knob) to load the battery
for more accurate measurement.
4. Place RED DMM probes indicated by red arrow, BLACK probe by black
arrow
Charge Indicator LED (LED should blink in
similar pattern to charger when charger is
connected)
Charger Interlock
15
+
Approx 48V DC
Note: If a valid voltage
Cannot be read, the electronics
built into the charge port may be
bad. In this event, Find the blue connector
which connects directly to the batteries.
Disconnect it, and measure battery voltage
Note: New mowers have a different pattern of Indexing pin.
When requesting repair parts, send a picture of this connector to ensure proper parts
For the charger and charge port
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Separating Connectors
Many of the connectors are sealed together with heat shrink tubing. To
separate the connectors, soften the heat shrink with a heat gun, then
peel the heat shrink tubing off with pliers as shown. Extra care is needed to
avoid damaging surrounding parts by the heat. Be careful of the batteries.
When reassembling connectors, be sure to apply new heat shrink tubing
and shrink with a heat gun to protect against elements and hold the connections together.
Extra care is needed to avoid damaging surrounding parts by the heat.
16
HEAT
GUN
CONNECTOR
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Control Panel
17
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Testing PTO (Power Take Off) Switch
3. Insert DMM probes where indicated.
When red button is PULLED OUT, the
switch is CLOSED (very LOW resistance or
continuity) typically 0 Ohms
4. When red button is PUSHED IN, the
switch is OPEN (very HIGH resistance or
no continuity) typical 12K Ohms when in circuit or open
when removed from circuit.
Note: Make sure
spade lugs are
secure. They should
be locked in place
and should not come
loose if the wires are
pulled on.
Note: 3 terminals are not connected
1. Mower Power OFF
2. DMM set to measure
Resistance
18
5V
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Testing RMO Switch
2
3. Touch leads where
indicated. LED should light
(polarity of probes does not
matter).
4. Set DMM to Resistance mode.
Switch is normally open (N.O.).
Measure continuity when
button held in. Measure high
resistance when released (10K).
(or open circuit when not connected)
1. DISCONNECT MAIN POWER FROM MOWER.
2. Set DMM to “Diode” mode.
Indicates unused terminals
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2.5V
5-6V
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Testing F-N-R Switch
2
456
Set switch in “F” position:
Continuity between 1 and 2.
Continuity between 4 and 5.
3. Set switch in Nposition:
No continuity between any pins.
(with no wires connected)
4. Set switch in Rposition:
Continuity between 2 and 3.
Continuity between 5 and 6.
2
456
1 3 3
1
1. DISCONNECT MAIN POWER TO MOWER
2. DMM set to measure Resistance
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