Page O-6
TROUBLESHOOTING AND DIAGNOSTICS
Repair and Service Manual
Read all of Section B and this section before attempting any procedure. Pay particular attention to all Notes, Cautions and Warnings.
B
12818 DC Bus High -
Hardware Detected
1. Battery Pack voltage is over
67 volts. NOTE: It is unlikely
this error will occur in the fac-
tory and very rarely in the field.
If it occurs in the field the most
likely cause is a loose power
wire or and internal controller
fault
1. Verify that all battery wires are securely
fastened and have less than 0.1 ohms resis-
tance between wire terminal and battery
post.
2. Check the battery voltage across all 4 bat-
teries, voltage should read 63 VDC
MAXI-
MUM
.
3. Check voltage across solenoid contacts. If
more than 3 VDC but less than 24 VDC pro-
ceed to step 3, if it does not fall in this range
follow
ACTION 3
.
4. Verify power resistor ohm reading is
between 0.2 and 0.5 ohms.
5. Remove resistor control module connec-
tion to controller B- terminal. If error status
changes follow
ACTION 1
.
1. Tighten or replace loose
or high resistance power
wire connections.
2. Replace power resistor.
3. Replace solenoid.
4. Replace resistor control
module.
5. If error continues,
replace the controller.
12833 DC Bus Low - Soft-
ware Detected
1. Controller DC Bus voltage
has dropped below 18 volts.
1. Verify that all battery wires are securely
fastened and have less than 0.1 ohms resis-
tance between wire terminal and battery
post.
2. Check the battery voltage across all 4 bat-
teries, voltage should read 42 VDC
Mini-
mum
.
3. Check voltage across solenoid contacts. If
more than 3 VDC but less than 24 VDC pro-
ceed to step 3, if it does not fall in this range
follow
ACTION 3
.
4. Verify power resistor ohm reading is
between 0.2 and 0.5 ohms.
5. Remove resistor control module connec-
tion to controller B- terminal. If error status
changes follow
ACTION 1
.
1. Tighten or replace loose
or high resistance power
wire connections.
2. Replace power resistor.
3. Replace solenoid.
4. Replace resistor control
module.
5. If error continues,
replace the controller.
16912 Motor Temp High
1. Vehicle is heavily loaded or
overloaded.
2. Motor temperature of greater
than or equal to 150°C (302°F),
NOTE: 1300 ohms equals a
motor temperature of 150°C.
1. Check external motor temperature, it
should be less than 120°C (248°F).
2. Check thermocouple resistance, it should
be more than 400 ohms and less than 1300
ohms. If not between these numbers perform
ACTION 3
.
1. Allow motor to cool.
2. Reduce payload or
travel grade.
3. Replace motor.
4. Replace the controller.
17168 Heat Sink Temp
High
1. Vehicle is heavily loaded or
overloaded.
2. Controller temperature is
greater than or equal to 120°C
(248°F).
1. Check the external heat sink temperature,
it should be less than 80°C (176°F).
1. Allow to cool.
2. Reduce payload or
travel grade.
3. Replace the controller.
20753 15V Supply Low
Voltage
1. Problem with the reverse
warning alarm (shorted)
2. Problem with controller’s
internal 15 volt supply.
1. With vehicle ’OFF’, unplug 23 pin connec-
tor from the controller and measure the
reverse alarm resistance, value should be
between 100 ohms and 500 ohms. Perform
ACTION 1
.
2. With vehicle ’OFF’, unplug 23 pin connec-
tor from the controller and measure the relay
resistance, value should be between 1 ohm
and 50 ohms. Perform
ACTION 2
.
1. Replace reverse alarm.
2. Replace controller.
CODE
DESCRIPTION
POSSIBLE CAUSES
DIAGNOSTIC STEP
ACTION (post diagnos-
tics)