Bendix Commercial Vehicle Systems MC-30 TRAILER ABS CONTROLLER - Manual (Page 30)

30
SECTION G - TROUBLESHOOTING WHEEL SPEED SENSORS
1
2
3
C2 Right Front WS +
A1 Right Front WS -
A2 Left Front WS +
A3 Left Front WS -
B1 Right Rear WS +
B2 Right Rear WS -
K J H G F E D C B A
30-Pin Connector
Make repairs or replace wiring or
wheel speed sensor. Reconnect all
connectors to the MC-30
™ controller
and sensor. Reset fault codes by
briefl y holding a magnet in place at
the RESET location of the diagnostic
display. Then rerun the power up
sequence. Go to Section A.
SEN LED and ABS indicator lamp
are on.
Turn off power to the MC-30 ™ controller
and remove the 30-pin connector.
Static Wheel Speed Sensor Faults
- Using a volt/ohm meter to measure
the connector pins of the faulted sensor,
verify 1500-2500 OHMS across sensor
connector pins. Verify no continuity
from sensor connector pins to ground.
Verify ignition power is not measured at
either sensor connector pins. Check for
corroded or damaged sensor and ECU
wiring and connectors. Verify proper
sensor lead routing and clamping.
If a circuit fault is found, isolate the
area needing repair by repeating the
measurements at all connections in the
wheel speed sensor circuit.
Wheel speed sensor fault identifi ed?
Dynamic Wheel Speed Sensor
Faults - Rotate the affected wheel
and verify a minimum of 0.8 VAC
sensor output @ 1 RPS across the
wheel speed sensor pins. A properly
positioned sensor can output more
than 2.0 VAC @ 1 RPS. Adjust speed
sensors to contact tone ring. Verify
condition and retention force of sensor
clips. Verify proper sensor lead
routing and clamping. Verify sensor
leads are twisted pair. Verify condition
of tone ring mounting and teeth.
Verify proper number of tone ring
teeth per sensed wheel. Verify proper
adjustment of wheel bearings. Verify
condition of foundation brakes.
Make repairs to wheel speed sensor
installation. Reconnect all connectors
to the MC-30
™ controller and sensor.
Reset fault codes by briefl y holding
a magnet in place at the RESET
location of the diagnostic display.
Then rerun the power up sequence.
Go to Section A.
NO
YES
B3 Left Rear WS +
C1 Left Rear WS -
E1 Ignition Power
E3 Brake Light Power
D2 Ground