Bendix Commercial Vehicle Systems EC-30 ABS/ATC CONTROLLER 2/08 - Manual (Page 27)

27
SECTION H - TROUBLESHOOTING WHEEL SPEED SENSORS
1
2
3
H3 Right Front WS -
H2 Right Front WS +
J2 Left Front WS -
J1 Left Front WS +
A1,A2,A3 Ground
B1,K2,K3 Power
K J H G F E D C B A
30-Pin Connector
B3 Right Mid WS -
B2 Right Mid WS +
C3 Left Mid WS -
C2 Left Mid WS +
E3 Right Rear WS -
E2 Right Rear WS +
F3 Left Rear WS -
F2 Left Rear WS +
F E D C B A
18-Pin Connector
1
2
3
Make repairs to wiring or replace
wheel speed sensor. Reconnect all
connectors to the EC-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
warning lamp are on.
Turn ignition off and remove the 30-pin
or 18-pin connector from the EC-30
™
controller.
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 effected wheel and verify for (a)
WS-20 speed sensors, a minimum of 0.8 VAC
sensor output @ 1 RPS across the wheel
speed sensor pins, or (b) for WS-24 speed
sensors, a minimum of 0.250 VAC @ 0.5
RPS. 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 EC-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