Bendix Commercial Vehicle Systems EC-17 ANTILOCK TRACTION CONTROL4/10 - Manual (Page 25)

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SECTION VII A - TESTING THE WHEEL SPEED SENSOR
START HERE
IGNITION ON, NOTE ILLUMINATED LED's.
RESET WITH A MAGNET, NOTE REACTION OF RED LEDs.
2nd TIME TO THIS POINT DURING TESTING?
GO TO SECTION VII PART B
AND BEGIN TESTING
YES
ANY RED LEDs ON? SAME RED LEDs ON?
YES NO
GO TO SECTION VII PART B
AND BEGIN TESTING
NO
NO
YES
GO TO SECTION IV.
RECONNECT CONNECTORS AT EC-17 ™ CONTROLLER
AND SPEED SENSOR, DO MAGNETIC RESET. NOTE
RED LEDs.
GO TO "INITIAL START-UP PROCEDURE"
YES
ARE ANY RED LEDs ILLUMINATED? GO TO SECTION III "INSPECTION FOR
ILLUMINATED LEDs."
NO
TURN IGNITION OFF AND CHECK FOLLOWING:
REMOVE 18 AND 30 PIN CONNECTOR FROM EC-17 ™ CONTROLLER. SET VOLT/
OHMMETER TO AC SCALE AND GENTLY PROBE SPEED SENSOR “PIN PAIRS” WHILE SPINNING
WHEEL BY HAND (30 PIN CONNECTOR “PIN PAIRS” J1&2 H2&3) (18 PIN CONNECTOR “PIN
PAIRS” B2&3, C2&3, E2&3, F2&3).
VOLTAGE OUTPUT FOR WS-20 ™ SENSOR SHOULD BE ABOVE 0.8 VOLTS AC AT 1 RPS.
VOLTAGE OUTPUT FOR WS-24 ™ SENSOR SHOULD BE ABOVE 0.250 VOLTS AC AT 0.5 RPS.
IF VOLTAGE IS BELOW THE MINIMUM CHECK ITEMS BELOW
A. CHECK "GAP" BETWEEN SPEED SENSOR AND EXCITER OR TONE RING. (GAP FOR
BENDIX ® WS-20 ™ SENSOR, SPEED SENDER IS BETWEEN 0 - .015 INCHES) IF SENSOR GAP
MUST BE ADJUSTED, CHECK FOR LOOSE OR WORN WHEEL BEARINGS BEFORE RE-
GAPPING SENSOR. REFER TO VEHICLE MAINTENANCE MANUAL FOR WORN BEARINGS.
CHECK SENSOR OUTPUT VOLTAGE.
B. IF SENSOR GAP IS CORRECT CHECK WHEEL BEARING FOR FREE PLAY TO VERIFY IT
COMPLIES TO MANUFACTURER’S RECOMMENDATIONS.
C. MAKE CERTAIN EXCITER OR TONE RING IS IN PLACE AND INSPECT CONDITION. CHECK
FOR MISSING OR DAMAGED TEETH AND THAT IT RUNS TRUE AND PERPENDICULAR TO
SENSOR FACE.
D. CHECK WIRING HARNESS AND CONNECTORS THAT RUN TO SENSOR.
E. CHECK FOR DRAGGING BRAKES (OVER ADJUSTED, TRAPPED AIR IN ACTUATOR, OUT OF
ROUND DRUMS, MALFUNCTIONING RETURN SPRINGS, PARKING BRAKE SYSTEM PROBLEMS,
ETC.) AND CORRECT AND RETEST.