Fault Code Guide

Right Front Wheel Sensor Troubleshooting (SID 002)
MID SID FMI Problem Test Test Result Action
136 002 10 Intermittent signal 7. Adjust the sensor. Using
the wheel sensor output
screen in Meritor PC
Diagnostics, spin the
wheel or drive the vehicle
and check for intermittent
or erratic signal.
Signal output OK Adjustment solved the problem.
Make sure brake chatter is not
causing the problem.
Signal output
incorrect
Check for intermittent wheel
sensor circuit connections. Cause
could be due to brake chatter.
Repair as needed.
136 002 11 Erratic signal Perform test 7.
136 002 12 Frequency too
high
8. Check sensor wiring
and connectors for
intermittent contact.
Wiring OK Suspect ECU at fault if problem
persists.
Wiring incorrect Repair wheel sensor circuit, as
needed.
Table 3, Right Front Wheel Sensor Troubleshooting (SID 002)
Left Rear Wheel Sensor Troubleshooting (SID 003)
MID SID FMI Problem Test Test Result Action
136 003 01 Incorrect sensor
air gap
1. Adjust the sensor.
Check the AC voltage
across pins 1 and 2 of the
black X2 ECU connector
while rotating the LR
wheel 30 rpm.
Voltage is 0.2 Vac
or greater
Sensor adjustment solved the
problem.
Voltage is less
than 0.2 Vac
Check for excessive wheel
bearing end play and hub runout.
Repair as needed.
136 003 02 Incorrect tire size Check for correct tire size and
mixed tire sizes. Check for correct
number of teeth on tone wheel.
Correct as needed.
136 003 03 Sensor shorted to
power
2. Measure the voltage
across pin 1 of the X3
(green) connector and a
good chassis ground.
Repeat the test between
pin 2 and ground.
Measurable
voltage at either
pin
Repair short to power in circuit(s)
377LR+ and 377LR– in chassis
harness and sensor cable.
If problem is in the sensor
harness, replace the sensor.
No voltage at
either pin
Repeat the test and check for
intermittent short to power in
circuits 377LR+ and 377LR–.
Suspect ECU is at fault if the
problem persists.
Meritor WABCO Pneumatic Antilock Braking System
(ABS)
42.00
ABS System Troubleshooting
Business Class M2 Workshop Manual, Supplement 2, June 2002 300/5