sensor ISUZU TROOPER 1995 Repair Manual

4-WHEEL ANTILOCK BRAKE SYSTEM (ABS) 5A4-39
CHART A-1 [):Eeft:j]
1) ABS WORKS FREOUENTL V BUT VEHICLE DOES NOT DECELERATE
PUT KEY OFF AND CONNECT PINOUT BOX.
WITH G SENSOR CONNECTOR DISCONNECTED,
CHECK CONTINUITY BETWEEN THE TERMINALS 1 AND 13
CHECK G SENSOR SINGLY (REFER TO CHART C-1)
IS THERE DAMAGE, OR POWDERED IRON STICKING
TO EACH WHEEL SPEED SENSOR/SENSOR RING?
IS
THE OUTPUT OF EACH WHEEL SPEED SENSOR
NORMAL?
(REFER TO CHART C-2)
• HARNESS BB04, BB16, BB17 ARE SHORTED
• REPAIR THE HARNESSES
REPLACE WHEEL SPEED
SENSOR OR REPAIR HARNESS

5A4-40 4-WHEEL ANTILOCK BRAKE SYSTEM (ABS)
CHART TA-1 I TECH 1 I
1) ABS WORKS FREOUENTL Y BUT VEHICLE DOES NOT DECELERATE ~
CONNECT TECH 1 I
I
MODE F6: WHEEL SENSORS MAKES SURE OF THE OUTPUT CONDITIONS OF EACH SENSOR
I
RETURN TO CHART A-1 I I REPLACE WHEEL SPEED SENSOR I
•

5A4-42 4-WHEEL ANTILOCK BRAKE SYSTEM (ABS)
CHART TA-2 I TECH 1 I
2) UNEVEN BRAKING OCCURS WHILE ABS WORKS
MAKE SURE OF THE OUTPUT CONDITIONS OF EACH SENSOR FOLLOWING THE PROCEDURE
DESCRIBED ON PAGE 5A4-31
REPAIR AND CHECK THE WHEEL SPEED
SENSOR (REFER TO CHART B-13, TB-13, C-2)
•

CHART A-5, TA-5 I):Eet<(] I TECH 1 I
5) BRAKING SOUND (FROM HYDRAULIC UNIT) IS HEARD WHILE NOT BRAKING
IS THIS THE FIRST VEHICLE START AFTER ENGINE
START? AND IS VEHICLE SPEED UNDER 10 KM/H
(6MPH)?
WHEN
DID IT OCCUR? 1. AT THE TIME OF SHIFT DOWN OR CLUTCH OPERATION 2. AT THE TIME OF LOW J.l DRIVE (ICE OR SNOW ROAD) OR ROUGH ROAD DRIVE 3. AT THE TIME OF HIGH-SPEED TURN 4. AT THE TIME OF PASSING CURB 5. AT THE TIME OF OPERATING ELECTRICAL
EQUIPMENT SWITCHES
6. AT THE TIME OF RACING THE ENGINE (OVER
5000 RPM)
IS THERE PLAY IN EACH SENSOR/WHEEL
SPEED SENSOR RINGS?
•
CHECK HARNESS/CONNECTOR FOR SUSPECTED
DISCONNECTION
• IF NO DISCONNECTION IS FOUND,
REPLACE EBCM
IT IS SELF-CHECKING SOUND NORMAL
UNDER ANY ONE CONDITION ABOVE, ABS MAY SOMETIME BE ACTUATED EVEN WHEN BRAKE
PEDAL IS NOT APPLIED
11 = Friction Unit

4-WHEEL ANTILOCK BRAKE SYSTEM (ABS) 5A4-49
2. Diagnostic trouble codes:
Choose and trace an appropriate flowchart by the numbers listed below to find fault and repair.
Code
Item Diagnosis Chart
No.
12 Start code Normal -
14 EBCM function Abnormality in input/output, operational and B-3
control circuits
15 Power voltage drop B-4
21 G-sensor Wiring disconnection B-5
22 Brake light switch Wiring disconnection B-6
23 Transmission input Input abnormality B-7
32 Motor & motor relay
Shorted or disconnected coil B-8
41 FL wheel valve
Shorted or disconnected coil/wiring
42 FR wheel valve
Shorted or disconnected coil/wiring B-9
44 Rear wheel valve Shorted or disconnected coil/wiring
45 Valve relay Shorted or disconnected coil/wiring B-10
51 FL wheel speed sensor Disconnected coil/wiring
52 FR wheel speed sensor Disconnected coil/wiring B-11
53 RL wheel speed sensor Disconnected coil/wiring
54
RR wheel speed sensor Disconnected coil/wiring
61 FL wheel speed sensor Shorted coil/wiring
62 FR wheel speed sensor Shorted coil/wiring B-12
63 RL wheel speed sensor Shorted coil/wiring
64 RR wheel speed sensor Shorted coil/wiring
65 Sensor signal input Wrong number of teeth B-13

5A4-54 4-WHEEL ANTILOCK BRAKE SYSTEM (ABS)
CHART B-5
G-SENSOR CIRCUIT (DIAGNOSTIC TROUBLE CODE 21)
. WITH THE VEHICLE ON A LEVEL SURFACE, TURN
THE KEY OFF • CONNECT THE PINOUT BOX MEASURE RESISTANCE BETWEEN TERMINALS
1 AND 13
I OVER 100n I o-1oo!l I
I
INSPECTG-SENSOR SINGLY(CHARTC-1) I . CHECK FOR SUSPECTED SHORT CIRCUIT IN
HARNESS AND CONNECTOR . IF NORMAL, REPLACE EBCM
~ $
HARNESS BETWEEN EBCM AND G-SENSOR IS REPLACE G-SENSOR I FAULTY I • REPAIR THE HARNESS
CHECK FOR SHORT CIRCUIT TO GROUND OF THE I HARNESS BETWEEN G-SENSOR AND EBCM (BB17)
•

4-WHEEL ANTILOCK BRAKE SYSTEM (ABS) 5A4-61
CHART B-11 [tE€f((]
SPEED SENSOR DISCONNECTION (DIAGNOSTIC TROUBLE CODE 51, 52, 53, & 54)
• WITH THE KEY TURNED OFF, CONNECT PINOUT BOX
• MEASURE THE FOLLOWING TERMINAL RESISTANCE
ACCORDING TO THE SPECIFIC DIAGNOSTIC TROUBLE
CODE STORED
CODE
51 (FL SENSOR) BETWEEN PINOUT BOX TERMINALS 4 AND 22 CODE 52 (FR SENSOR) BETWEEN PINOUT BOX TERMINALS 21 AND 23 CODE 53 (RL SENSOR) BETWEEN PINOUT BOX TERMINALS 8 AND 9 CODE 54 (RR SENSOR) BETWEEN PINOUT BOX TERMINALS 24 AND 26
I
l I 0.8K-1.3Kn I OTHER I
l I • CHECK FOR FAULTS IN HARNESS BETWEEN MEASURE EACH SENSOR RESISTANCE AT I SPEED SENSOR AND EBCM THE SENSOR CONNECTOR
• FAULT FOUND: REPAIR, AND PERFORM I SYSTEM SELF-CHECK I I • NO FAULT FOUND: REPLACE EBCM o.BK-1.3Kn I l OTHER j
I I REPAIR HARNESS I REPLACE SENSOR I ABNORMALITY BETWEEN SENSORS AND EBCM

5A4-62 4-WHEEL ANTILOCK BRAKE SYSTEM (ABS)
CHART B-12 tJEe©]
SPEED SENSOR SHORT CIRCUIT (DIAGNOSTIC TROUBLE CODE 61, 62, 63, & 64) ~
WITH THE KEY TURNED OFF, CONNECT PINOUT BOX
MEASURE THE FOLLOWING TERMINAL RESISTANCE
ACCORDING TO THE SPECIFIC DIAGNOSTIC TROUBLE CODE STORED:
CODE 61 (FL SENSOR) BETWEEN PINOUT BOX TERMINALS 4 AND 22 CODE 62 IFR SENSOR) BETWEEN PINOUT BOX TERMINALS 21 AND 23 CODE 63 IRL SENSOR) BETWEEN PINOUT BOX TERMINALS 8 AND 9 CODE 64 (RR SENSOR) BETWEEN PINOUT BOX TERMINALS 24 AND 26
DAMAGE
AND POWERED IRON STICKING TO SENSOR/SENSOR RING?
CHECK FOR FAULTS IN
HARNESS BETWEEN SPEED SENSOR AND EBCM
FAULT FOUND: REPAIR, AND PERFORM SYSTEM SELF-CHECK NO FAULT FOUND:
REPLACE EBCM
REPAIR HARNESS BETWEEN SENSORS AND EBCM
•

CHART B-13, TB-13 l)EeR:[I I TECH 1 I
SENSOR SIGNAL INPUT ABNORMALITY (DIAGNOSTIC TROUBLE CODE 65)
SELECT F3: SNAP SHOT MANUAL TRIGGER
WITH
WHEEL SPEED DATA DISPLAYED, RUN THE *1 VEHICLE WHEN SPEED HAS ARRIVED AT 30 KM/H
(18 MPH), PRESS F9 KEY
CHECK SPEED DATA ON EACH WHEEL (REFER TO THE CRITERIAL GIVEN BELOW)
ONLY THE ABNORMAL WHEEL SHOULD
FOLLOW THE NEXT FLOWCHART
IS THERE PLAY IN SENSOR/SENSOR ROTOR? -I)Eel{[l ALL THE WHEELS SHOULD FOLLOW THE FOLLOWING FLOWCHART
IS THERE POWDERED IRON STICKING
TO SENSOR/SENSOR ROTOR?
cill
~
Sensor Signal Abnormality Criteria using TECH 1 --------,
1) While driving, the speed of one or two wheels is 25% or more higher than that of
the other wheels.
2) The speed of one or two wheels is 10 km/h (6 mph) or more higher than that of the
other
wheels.
3) During steady driving, wheel speed changes abruptly.
* 1 The vehicle must run on a level paved road.

5A4 -64 4-WHEEL ANTILOCK BRAKE SYSTEM (ABS)
UNIT INSPECTION PROCEDURE
This section describes the following inspection procedures referred to during "SYMPTOM DIAGNOSIS" and
"DIAGNOSIS BY 'ABS' WARNING LIGHT ILLUMINATION PATTERN":
without TECH 1 with TECH 1
G-sensor
Unit Inspection Chart C-1 -
Sensor Output Inspection Chart C-2 Chart TC-2
Transfer
SW Inspection Chart C-3 Chart TC-3
Transmission
SW Inspection Chart C-4 Chart TC-4
•