wheel ISUZU TROOPER 1995 Workshop Manual

REAR WHEEL ANTILOCK BRAKE SYSTEM 5A3-13
Continued from the previous page
• CHECK AND REPAIR ALL CIRCUITS FUSE IS PROTECTING FOR SHORTS TO GROUND. REPLACE FUSE, AND RECHECK THE SELF CHECK. •
DISCONNECT
THE EBCM HARNESS CONNECTOR FROM
EBCM, AND TURN THE IGNITION KEY TO THE ON POSITION, CHECK FOR VOLTAGE BETWEEN PIN (13) AND CHASSIS GROUND WHILE SHAKING THE HARNESS.
CONSTANT READING OF VOLTAGE OVER 9V CONSTANT READING OF VOLTAGE UNDER9V
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EBCM -
Electronic Brake Control Module

5A3-14 REAR WHEEL ANTILOCK BRAKE SYSTEM
Continued from the previous page
• CHECK FOR FUSE C-14 IN THE FUSE BOX OF INSTRUMENT PANEL
FUSE IS BLOWN. FUSE IS OK.
•
CHECK AND REPAIR ALL CIRCUITS FUSE IS PROTECTING FOR SHORTS TO GROUND. REPLACE FUSE, AND RECHECK THE SELF CHECK.
• DISCONNECT THE EBCM HARNESS CONNECTOR FROM EBCM, AND CHECK FOR VOLT AGE BETWEEN PIN (1 0) AND CHASSIS GROUND WHILE SHAKING THE HARNESS.
CONSTANT READING
OF VOLTAGE OVER 9 V
• CHECK FOR RESISTANCE BETWEEN PIN (7) AND CHASSIS
GROUND WHILE SHAKING THE HARNESS.
CONSTANT READING
OF OVER 1 OOK OHMS
REPLACE THE EBCM, AND RECHECK SYSTEM. CONSTANT
READING
OF VOLTAGE UNDER 9 V
REPAIR OPEN CIRCUIT
CONSTANT
READING OF UNDER 100K OHMS
REPAIR SHORT CIRCUIT TO
THE GROUND. ERRATIC
VOLTAGE
READING.
REPAIR THE HARNESS.
ERRATIC RESISTANCE READING.
REPAIR
THE HARNESS.
EBCM = Electronic Brake Control Module
•

REAR WHEEL ANTILOCK BRAKE SYSTEM 5A3-15
CHART D
Rr. ABS and Brake Lights Flashing
• TURN THE IGNITION KEY TO THE OFF POSITION, AND DISCONNECT THE EBCM HARNESS CONNECTOR FROM EBCM AND IGN. KEY ON CHECK FOR VOLTAGE AT PIN {13) OF EBCM HARNESS CONNECTOR AND CHASSIS GROUND WHILE
SHAKING THE BODY HARNESS AND REAR BODY HARNESS.
REPAIR THE HARNESS FOR OPEN CIRCUIT, AND RECHECK • DISCONNECT BATTERY, AND CHECK FOR RESISTANCE AT PIN {7) OF THE EBCM HARNESS CONNECTOR AND CHASSIS GROUND WHILE SHAKING THE BODY
HARNESS AND REAR BODY HARNESS.
THE SYSTEM.
•
CHECK FOR RESISTANCE AT PIN {15) OF EBCM HARNESS
CONNECTOR, AND CHASSIS GROUND WHILE SHAKING THE BODY HARNESS AND REAR BODY HARNESS.
REPAIR OPEN CIRCUIT
IN WIRE TO PIN {15) CONNECTOR, AND RECHECK THE SYSTEM.
EBCM = Electronic Brake Control Module

5A3-16 REAR WHEEL ANTILOCK BRAKE SYSTEM
CHART E
Rear Wheels Lock with Hard Stops
(Rr. ABS and Brake Lights Self Check Properly)
• APPLY THE BRAKE PEDAL AND CHECK FOR STOP LIGHTS.
STOP LIGHTS WILL NOT ILLUMINATE.
CHECK STOP LIGHT SWITCH OR CIRCUIT, AND REPAIR AS
NECESSARY, AND RECHECK IT.
EXCITER RING IS MISSING, OR TEETH ARE MISSING.
REPLACE
THE EXCITER RING.
VOLTAGE
UNDER 650 mV ON AC SCALE
REPLACE
THE SPEED SENSOR, AND RECHEK SENSOR
OUTPUT.
REAR BRAKES OK.
REPLACE THE EBCM.
STOP LIGHTS OK.
• REMOVE THE SENSOR FROM THE REAR AXLE CASE, AND CHECK FOR MISSING EXCITER RING, OR TEETH MISSING.
EXCITER
RING IS PRESENT, AND TEETH ARE INTACT.
• REINSTALL
THE SENSOR AND RAISE REAR WHEELS TO
SAFELY CLEAR THE FLOOR.
• START ENGINE, AND TURN REAR WHEEL AT 5 MPH.
• REMOVE THE LEFT HAND KICK PANEL, AND USING A
VOLTMETER SET ON THE AC SCALE, CHECK FOR VOLTAGE AT THE TWO PINS OF THE SENSOR TEST
CONNECTOR.
VOLTAGE
OVER 650 mV ON AC SCALE
• REINSTALL
THE KICK PANEL, AND CHECK THE REAR BRAKE FOR MECHANICAL PROBLEMS SUCH AS GRABBING, LOCKING OR PULLING.
REAR BRAKES LOCK, GRAB OR PULL.
REPAIR THE REAR BRAKE PROBLEMS.
EBCM = Electronic Brake Control Module
•

REAR WHEEL ANTILOCK BRAKE SYSTEM 5A3-17
DIAGNOSTIC TROUBLE CODES
FLASHOUT CODES CHART
CONDITION ACTION TO
TAKE
Rr. ABS light flashes 2 times. See Flashout Diagnostic
(High resistance
isolate circuit or malfunctioning EBCM) Trouble Code (DTC) 2
Rr. ABS light flashes 3 times. See Flashout DTC 3
(High resistance
dump circuit or malfunctioning EBCM)
Rr. ABS light flashes 4 times.
See Flashout DTC 4
(Closed rear wheel antilock valve switch)
Rr. ABS light flashes 5 times.
See Flashout DTC 5
System dumps
too many times in 2WD (2WD and 4WD vehicles)
condition
Occurs while making normal or hard stops. Rear brake may lock.
Rr. ABS light flashes 6 times.
See Flashout DTC 6
(Erratic speed sensor reading
while driving)
Rr. ABS light flashes 7 times. See Flashout DTC 7
Isolation output missing or antilock valve wiring shorted to ground
Rr. ABS light flashes 8 times.
See Flashout DTC 8
Dump
output missing or antilock valve wiring shorted to ground
Rr. ABS light flashes 9 times. See Flashout DTC 9
(High sensor resistance)
Rr. ABS light flashes 10 times.
See Flashout DTC 1 0
(Low sensor resistance)
Rr. ABS light flashes 11 times.
See Flashout DTC 11
Stop light switch circuit defective, condition indicated only when driving
above
56 km/h (35 mph)
Rr. ABS light flashes 13 times.
See Flashout DTC 13
(Speed processor check EBCM)
Rr. ABS light flashes 14 times.
See Flashout DTC 14
(Program check
EBCM)
Rr. ABS light flashes 15 times.
See Flashout DTC 15
(Memory failure EBCM)
NOTE:
• Codes 1, 12 and over 15 are not utilized for the diagnostic mode.
EBCM = Electronic Brake Control Module

5A3-18 REAR WHEEL ANTILOCK BRAKE SYSTEM
DIAGNOSIS PROCEDURE
FLASHOUT DIAGNOSTIC TROUBLE CODE 2
(HIGH RESISTANCE ISOLATE CIRCUIT OR MALFUNCTIONING EBCM)
Antilock valve
Isolate.
Retest SW.
(EBCM)
Dump
• DISCONNECT THE BATIERY GROUND CABLE.
• DISCONNECT THE EBCM HARNESS CONNECTOR FROM EBCM, AND
CHECK FOR RESISTANCE BETWEEN EBCM HARNESS CONNECTOR PIN (1) AND CHASSIS GROUND WHILE SHAKING THE HARNESS.
CONSTANT READING
OF RESISTANCE 3 TO 6 OHMS
CHECK EBCM VALVE AND GROUND CONNECTION
NO
PROBLEM IN EBCMIVALVE AND GROUND CONNECTION.
CONNECT
EBCM TO HARNESS CONNECTOR THEN TURN IGNITION ON.
NO CODE
2 INDICATED
REPLACE ANTILOCK VALVE AND RECHECK
THE SELF CHECK AND RETEST VEHICLE.
PROBLEM FOUND REPAIR CONNECTION(S) AND/OR GROUND
CODE 2 RETURNS
REPLACE EBCM AND
RECHECK THE SELF CHECK.
EBCM
= Electronic Brake Control Module
4!1
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REAR WHEEL ANTILOCK BRAKE SYSTEM 5A3-19
Continued from the previous page
• DISCONNECT ANTI LOCK VALVE HARNESS CONNECTOR, AND CHECK FOR RESISTANCE BETWEEN GROUND PIN (3) OF VALVE HARNESS CONNECTOR AND CHASSIS
HARNESS GROUND WHILE SHAKING THE HARNESS.
CONSTANT READING
RESISTANCE
OVER 1 OHM OF
REPAIR OPEN CIRCUIT IN VALVE GROUND WIRE HARNESS OR LOOSE CONNECTOR PINS, AND RECHECK THE SELF CHECK.
Valve connector
CONSTANT READING OF RESISTANCE UNDER 1 OHM
•
CHECK FOR RESISTANCE BETWEEN ISOLATION PIN (4) AND
GROUND PIN (3) OF VALVE
CONNECTOR.
Harness connector
REPAIR OPEN ISOLATION SOLENOID WIRE FROM THE VALVE TO EBCM OR LOOSE PINS IN CONNECTOR, AND RECHECK THE SELF CHECK.
REPLACE THE ANTILOCK VALVE, AND RECHECK THE SELF CHECK.
EBCM ~ Electronic Brake Control Module

5A3-20 REAR WHEEL ANTILOCK BRAKE SYSTEM
FLASHOUT DIAGNOSTIC TROUBLE CODE 3
(HIGH RESISTANCE DUMP CIRCUIT OR MALFUNCTIONING EBCM)
Anti lock valve
Isolate.
Reset SW.
(EBCM)
Dump
• DISCONNECT THE BATTERY GROUND CABLE.
• DISCONNECT EBCM HARNESS CONNECTOR FROM EBCM,
AND CHECK FOR RESISTANCE BETWEEN EBCM HARNESS CONNECTOR PIN (9) AND CHASSIS GROUND WHILE SHAKING THE HARNESS.
CONSTANT READING
OF RESISTANCE 1 TO 3 OHMS
CHECK EBCM
VALVE AND GROUND CONNECTION
NO
PROBLEM IN EBCMIVALVE AND
GROUND CONNECTION.
CONNECT EBCM TO HARNESS CONNECTOR
THEN TURN IGNITION ON.
NO CODE 31NDICATED
REPLACE ANTILOCK
VALVE AND RECHECK THE SELF CHECK AND RETEST VEHICLE.
PROBLEM FOUND REPAIR CONNECTION(S) AND/OR GROUND
CODE 3 RETURNS
REPLACE EBCM
AND RECHECK THE SELF
CHECK.
EBCM
~ Electronic Brake Control Module
4Q
1.5 !l
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REAR WHEEL ANTILOCK BRAKE SYSTEM 5A3-21
Continued from the previous page
• DISCONNECT ANTILOCK VALVE HARNESS CONNECTOR, AND CHECK FOR RESISTANCE BETWEEN GROUND PIN (3) OF VALVE HARNESS CONNECTOR AND CHASSIS
HARNESS GROUND WHILE SHAKING THE HARNESS.
CONSTANT READING
RESISTANCE
OVER 1 OHM
Valve
connector
OF CONSTANT READING OF RESISTANCE UNDER 1 OHM
•
CHECK FOR RESISTANCE BETWEEN DUMP PIN (1) AND
GROUND PIN (3) OF VALVE
CONNECTOR Harness
connector
REPAIR OPEN DUMP SOLENOID WIRE FROM THE VALVE TO THE EBCM OR LOOSE PINS IN THE CONNECTOR, AND RECHECK THE SELF CHECK.
REPLACE THE ANTILOCK VALVE, AND RECHECK THE SELF CHECK.
EBCM -Electronic Brake Control Module

5A3-22 REAR WHEEL ANTILOCK BRAKE SYSTEM
FLASHOUT DIAGNOSTIC TROUBLE CODE 4
(CLOSED REAR WHEEL ANTILOCK VALVE SWITCH)
Isolate.
Reset SW.
(EBCM)
Dump
Valve connector
Anti lock valve
• DISCONNECT ANTILOCK VALVE CONNECTOR, AND CHECK FOR RESISTANCE BETWEEN THE VALVE CONNECTOR RESET SWITCH PIN {2) AND THE VALVE BODY.
4Q
CONSTANT READING OF RESISTANCE UNDER 10K OHMS
CONSTANT READING OF RESISTANCE OVER 10K OHMS
REPLACE ANTILOCK VALVE, AND RECHECK THE SELF CHECK.
Valve connector
• CHECK FOR RESISTANCE BETWEEN THE VALVE CONNECTOR RESET SWITCH PIN {2) AND GROUND PIN (3).
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