1995 ISUZU TROOPER Workshop Manual

4-WHEEL ANTILOCK BRAKE SYSTEM (ABS) 5A4-7
BASIC DIAGNOSTIC FLOW CHART
I CUSTOMER COMPLAINT I
I
' I QUESTIONING TO CUSTOMER 1
I
BASIC INSPECTION I REFER TO "BASIC INSPECTION PROCEDURE"
+
I
I TECH 1 AVAILABLE I
I TECH 1 UNAVAILABLE REFER TO "DIAGNOSIS BY 'ABS'
t
WARNING LIGHT ILLUMINATION
PATTERN"
I MAKE SURE OF DTC BY I MODE F2: TROUBLE CODE I CHECK IF THE DTC IS STORED OR NOT
I I
I DTC I I NO DTC I I NO
DTC I
I DTC I
I I
I TEST
DRIVEl
I
I W/L NOT LIT I I W/L IS LIT I
I
I TROUBLE DIAGNOSIS I BASED ON SYMPTOM I LOCATING THE FAUL Tj BYDTC
REFER TO "SYMPTOM
DIAGNOSIS"
I REPAIR OF FAUL TV PART I
I
CHECK TRANSMISSION/TRANSFER~ INPUT (CHART C-3, C-4, TC-3, TC-4)
ELIMINATION
OF DTC I
I
INSPECTION OF "ABS" W/L ILLUMINATION
1 PATTERN WITH IGNITION SW "ON"
+ I TEST DRIVE ~ REPEAT THE DIAGNOSIS IF
THE SYMPTOM OR DTC
APPEARS AGAIN
I FINISHED I
DTC = Diagnostic Trouble Code

5A4-8 4-WHEEL ANTILOCK BRAKE SYSTEM (ABS)
BASIC INSPECTION PROCEDURE
1. Basic Inspection of Service Brake
VISUALL V CHECK PAD & ROTOR
2. Inspection of Transfer Switch
3. Ground Inspection
PUT THE KEY SWITCH ON AND
SHIFT T/F LEVER TO 4H
CHECK IF 4WD LIGHT IS LIT
VISUALL
V CHECK ASS-RELATED
GROUND POINTS
•

4-WHEEL ANTILOCK BRAKE SYSTEM (ABS) 5A4-9
MEMO

5A4-10 4-WHEEL ANTILOCK BRAKE SYSTEM (ABS)
TECH 1 TOOL
TECH 1 is an effective tool for the diagnosis of
electrical fault of Antilock Brake System (ASS) and
system check.
Although you can completely
diagnose the system without a TECH 1, using the
tool is quicker. In the following procedures, the
!TECH 11 symbol shows where the TECH 1 is used.
The
t::nettll symbol means the tool is not used.
1. WHAT CAN BE DONE WITH TECH 1
ON TECH 1
TECH 1 is a hand-held tester (Fig. 5A4-4).
Connected
to the Data Link Connector (DLC)
installed in the vehicle, it communicates with
ABS control unit (EBCM), thereby conducting
various diagnoses and tests.
Fig. 5A4-4
For this
vehicle, use ISUZU '90-'94
TRANSMISSION/ASS cartridge.
TECH 1 can check the following items:
(1) Input values of EBCM sensors and
switches, and
working conditions of
solenoid valves.
(2) Diagnostic Trouble Code (DTC) No.
(3) Incoming/outgoing data records.
(4) The function of ABS through the
operation
of the motor and solenoid
valves.
(5) Clearing DTCs stored in EBCM.
How to connect TECH 1 with the vehicle (Fig.
5A4·5, 5A4-6)
(1) Insert the program cartridge (TK02500B-1)
securely
into the TECH 1 main unit (J-38770-1).
(2) Attach the adapter to the cable.
(3) Plug the ISUZU 3-pin adapter (T A-02279-8) into
the adapter.
(4) Insert one end of the power plug into the TECH
1 and the other end into the cigarette lighter of
the vehicle.
The power plug may as well be coupled
directly
to the battery using the battery cable
adapter (J-38770-4).
(5) Turn the ignition key OFF, and connect TECH 1
with DLC (Orange colored).
Fig. 5A4-5
Data link Connector (Orange)
Fig. 5A4-6

4-WHEEL ANTILOCK BRAKE SYSTEM (ABS) 5A4-11
2. HOW TO USE TECH 1
Operating procedure for TECH 1
After connecting with the vehicle, turn the ignition
key
ON and follow the flow chart.
W CAUTION:
When mounting and removing "ISUZU '90 -'94
TRANSMISSION/ ABS CARTRIDGE", make sure
that no power is supplied to TECH 1. Press the
detents on the outside of the cartridge to unlock
it (Fig. 5A4-7).
Fig. 5A4-7

5A4-12 4-WHEEL ANTILOCK BRAKE SYSTEM (ABS)
Procedure to follow until ABS data is displayed:
ISUZU 90-94
TRANSMISSION/ASS
C YES)
ISUZU 90-94
TRANSMISSION/ASS
SELECT
MODEL YEAR:l99?
SELECT MODEL
UBSCG), UC, UX
MODEL YEAR:l994
CYES/NO)
STOP ENGINE
TURN ON IGNITION
C YES)
SELECT
ELECTRONIC DRIVE
TRAIN SYSTEM?
CYES/NO)
SELECT
ELECTRONIC
CHASSIS SYSTEM?
CYES/NO)
SELECT BY YES
*ABS-2E
WATING
FOR DATA ON
ABS-2E
COMPARE ISUZU
PART-NO
********** WITH
CHART 3 CYES/NO)
Press the YES key.
Input the model year of the vehicle.
(Input
4.)
Continue to press the NO key until UBS(G) is displayed. Then press the
YES key.
Stop the engine and turn the ignition key
ON. Then press the YES key.
Do you check the drive train? As ABS system is
not the drive train, press
the
NO key.
Do you check the chassis? As ABS
is in the chassis system, press the YES
key.
To
call data from control unit, press the YES key.
Now calling data out of control unit.
Identify the part No. of the control unit, and then press the YES key.

ABS-2E
NO TROUBLE CODE
SELECT MODE
FO:DATA LIST
F1: NOT USED
F2:TROUBLE CODE
SELECT MODE
F3:SNAP SHOT
F4:CLEAR CODE
F5:ACTUATOR TEST
SELECT MODE
F6:WHEEL SENSORS
*note 1
ABS-2E
NO DATA!
CHECK ALDL CONN.
SEE CHART 1
4-WHEEL ANTILOCK BRAKE SYSTEM (ABS) 5A4-13
There is no trouble code in ABS system.
(In case of trouble, trouble code is displayed)
Select
desired mode (see following explanation of modes). (Scroll up and
down by key III. m operation.)
Chances are
that the picture as shown in the box appears next to the 8th
picture.
It is displayed when there is no communication between TECH 1
and the EBCM. The
following causes are considered:
CHART
1:
There are three different situations in which EBCM does not communicate
with TECH 1:
1) Disconnection of Data Link Connector (ALDL) Harness
Check
to see "ABS" warning light is normally actuated with IGN being
ON. lfthe light is not actuated, harness abnormality is suspected.
2) While driving (wheel speed values inputted)
No problem in running the vehicle after communicating with TECH 1
while the vehicle stops.