1997 MITSUBISHI TRITON warning

ABS <2WD> ± Troubleshooting35B-5
TROUBLESHOOTING35201110143
STANDARD FLOW OF DIAGNOSTIC TROUBLESHOOTING
Refer to GROUP 00 ± How to Use Troubleshooting/Inspection Service Points.
NOTES WITH REGARD TO DIAGNOSIS
The phenomena listed in the following table are not abnormal.
PhenomenonExplanation of phenomenon
System check soundWhen starting the engine, a thudding sound can sometimes be heard coming from inside
the engine compartment, but this is because the system operation check is being
performed, and is not an abnormality.
ABS operation sound1. Sound of the motor inside the ABS hydraulic unit operation. (whine)
2. Sound is the generated along with vibration of the brake pedal. (scraping)
3. When ABS operates, sound is generated from the vehicle chassis due to repeated
brake application and release.
(Thump: suspension; squeak: tyres)
ABS operation
(Long braking distance)For road surfaces such as snow-covered roads and gravel roads, the braking distance for
vehicles with ABS can sometimes be longer than that for other vehicles. Accordingly, advise
the customer to drive safely on such roads by lowering the vehicle speed and not being too
overconfident.
Shock during system
operation checkShock may be felt when the brake pedal is depressed slightly at a low driving speed. This
occurs due to ABS operation check (initial check at a vehicle speed of 8 km/h), and does
not indicate any malfunction.
Diagnosis detection condition can vary depending on the diagnosis code.
Make sure that checking requirements listed in the ªCommentº are satisfied when checking the trouble
symptom again.
DIAGNOSIS FUNCTION35201120108
DIAGNOSIS CODES CHECK
Read a diagnosis code by the MUT-II or ABS warning lamp.
(Refer to GROUP 00 ± How to Use Troubleshooting/Inspection
Service Points.)
ERASING DIAGNOSIS CODES
Refer to GROUP 00 ± How to Use Troubleshooting/Inspection
Service Points.

ABS <2WD> ± Troubleshooting35B-11
Code No. 51 Valve relayProbable cause
When the ignition switch is turned to ON, the ABS-ECU switches the valve relay
off and on during the initial check. In that way, the ABS-ECU compares the signals
sent to the valve relay with the voltage in the valve power monitor line. That is how
to check if the valve relay is operating normally. The ABS-ECU always checks if
current flows in the valve power monitor line, too. It determines that there is an open
circuit when no current flows. If no current flows in the valve power monitor line,
this diagnosis code is output.
Malfunction of valve relay

Malfunction of wiring harness or connector

Malfunction of ABS-ECU

Malfunction of hydraulic unit
NOTE
Whenever reading the diagnosis codes using the ABS warning lamp (Refer to GROUP 00 ± How to
Use Troubleshooting/Inspection Service Points), this diagnosis code will be output. That is not a malfunction
but because the valve relay connector is disconnected. After repairing all other malfunctions, connect
the valve relay connector again to check the valve relay. Then check that the ABS warning lamp does
not illuminate. If it illuminates, the valve relay may be defective. So carry out the following procedure.
Valve relay check. (Refer to P. 35B-28.)NGReplace the valve relay.
OK
Measure at valve relay connector A-39.

Disconnect the connector and
measure at the harness side.

Voltage between 6 ± body earth
OK:System voltageNGCheck the harness between fusible link
No. 11 and valve relay, and repair if nec-
essary.
OK
Measure at ABS-ECU connector C-62
and C-64.

Disconnect the connector and
measure at the harness side.

Resistance between 26 ± 37
OK:60 ± 120 WNGCheck the following connector.
A-39OKCheck trouble symptoms.
NG
Check the harness between valve relay
and ABS-ECU, and repair if necessary.
OK
Measure at ABS-ECU connector C-64.

Disconnect the connector and
measure at the harness side.

Continuity between 48 ± body earth
OK:ContinuityNGCheck the harness between the valve
relay and ABS-ECU, and repair if neces-
sary.
OK
Check the following connector.
C-64OKCheck trouble symptoms.NGReplace the ABS-ECU.

ABS <2WD> ± Troubleshooting35B-14
INSPECTION CHART FOR TROUBLE SYMPTOMS35201140142
Get an understanding of the trouble symptoms and check according to the inspection procedure chart.
Trouble symptomsInspection
procedure No.Reference
page
Communication with MUT-II
is notpossible
Communication with all systems is not possible.135B-15
is not ossible.
Communication with ABS only is not possible.235B-15
When the ignition key is turned to ªONº (engine stopped), the ABS warning lamp does
not illuminate.335B-16
After the engine starts, the ABS warning lamp remains illuminated.435B-16
When the ignition key is turned to ªSTARTº, the ABS warning lamp does not illuminate.535B-17
After the ignition key is turned to ªONº, the ABS warning lamp blinks twice, and when
turned to ªSTARTº, it illuminates. When returned to ªONº, the lamp flashes once, and
then switches off.635B-17
Faulty ABS operationUnequal braking power on both sides735B-18
Insufficient braking power
ABS operates under normal braking conditions
ABS operates before vehicle stops under normal
braking conditions
Large brake pedal vibration (Caution 2.)±±
Caution
1. If steering movements are made when driving at high speed, or when driving on road surfaces
with low frictional resistance, or when passing over bumps, the ABS may operate even though
sudden braking is not being applied. Because of this, when getting information from the customer,
check if the problem occurred while driving under such conditions as these.
2. During ABS operation, the brake pedal may vibrate or may not be able to be depressed. Such
phenomena are due to intermittent changes in hydraulic pressure inside the brake line to prevent
the wheels from locking and is not an abnormality.

ABS <2WD> ± Troubleshooting35B-16
Inspection Procedure 3
When ignition key is turned to ºONº (engine stopped),
ABS warning lamp does not illuminate.
Probable cause
When current flows in the ABS-ECU, the valve relay turns from off to on, off and
back to on again as the initial check. So the ABS warning lamp will illuminate twice
when the valve relay is off even if there is a problem with the circuit between the
ABS warning lamp and the ABS-ECU.
Therefore, if the lamp does not illuminate, the cause may be: an open circuit in the
lamp power supply circuit, a blown lamp bulb, an open circuit in both the circuit between
the ABS warning lamp and the ABS-ECU and in the circuit between the ABS warning
lamp and the valve relay.
Blown fuse

Burnt out ABS warning lamp bulb

Malfunction of wiring harness or connector
OK
Check trouble symptoms.NGReplace the combination meter. NG
Repair
OK
Check the following connectors.
C-88, C-79, C-06, C-05 and C-02
OK
Check the harnesses between the valve
relay and connector C-02 and between
the ABS-ECU and connector C-02. Re-
pair if necessary.
OK
Measure at connector C-02:

Disconnect the connector and
measure at the male pin.

Ignition switch: ON

Does the ABS warning lamp
illuminate when terminal (3) is
earthed?
OK:IlluminatesNGCheck whether the ABS warning lamp
bulb is burnt out.NGReplace the ABS warning lamp bulb.
Fuse inspection, Multi-purpose fuse No.
11NGRefer to GROUP 00 ± Inspection Ser-
vice Points for a Blown Fuse.
Inspection Procedure 4
Even after the engine is started, the ABS warning lamp
remains illuminated.
Probable cause
The cause is probably a short-circuit in the ABS warning lamp illumination circuit.
Malfunction of combination meter

Malfunction of ABS-ECU

Malfunction of wiring harness
NOTE
This trouble symptom is limited to cases where communication with the MUT-II is possible (ABS-ECU
power supply is normal) and the diagnosis code is a normal diagnosis code.
No
Check the harnesses between the combination meter and the ABS-
ECU and between the combination meter and the valve relay. Repair,
if necessary.
No

Disconnect ABS-ECU connector C-64.

Disconnect valve relay connector A-39.

Ignition switch: ON

Does the ABS warning lamp switch off?Ye sReplace the ABS-ECU.
Disconnect connector C-02 and turn the ignition switch to ON.

Does the ABS warning lamp remain illuminated?Ye sReplace the combination meter.

ABS <2WD> ± Troubleshooting35B-17
Inspection Procedure 5
When ignition key is turned to ºSTARTº, ABS warning
lamp does not illuminate.
Probable cause
Current does not flow in the ABS-ECU when the ignition switch is turned to START.
Current flows in the ABS warning lamp even when the ignition switch is turned to
START. Therefore, the valve relay, which current is supplied through the ABS-ECU,
turns off when the ignition switch is at START. However, the warning lamp circuit
of the valve relay must turn on in turn. So the cause must be a defective circuit
on valve relay side.
Malfunction of wiring harness or connector

Malfunction of ABS-ECU
ABS valve relay check (Refer to
P.35B-28.)NGReplace the ABS valve relay.
OK

Disconnect valve relay connector
A-39.

Disconnect ABS-ECU connector
C-64.

Ignition switch: ON

Voltage between valve relay
harness-side connector terminal (3)
and body earth
OK:System voltageNGCheck the following connector and
diode.
C-02 and C-05NG
Repair
OK
Check trouble symptoms.NGCheck the harness between the com-
bination meter and valve relay, and re-
pair if necessary.
OK
Check the following connector.
A-39NG
Repair
OK
Check trouble symptoms.NGCheck the harness between the valve
relay and earth, and repair if necessary.
Inspection Procedure 6
The ABS warning lamp flashes twice after the ignition key
is turned to ºONº. The lamp illuminates when the ignition
key is turned to ºSTARTº, and when the key is returned to
ºONº, it flashes once.
Probable cause
The ABS-ECU causes the ABS warning lamp to illuminate during the initial check
(approx. 3 seconds). During the initial check, the valve relay turns from off to on,
off and back to on again. If there is an open circuit in the harness between the ABS-ECU
and the ABS warning lamp, the lamp will illuminate only when the valve relay is OFF
during valve relay test, etc.
Malfunction of wiring harness or connector

Malfunction of ABS-ECU

Disconnect valve relay connector
A-39.

Disconnect ABS-ECU connector
C-64.

Ignition switch: ON

Voltage between ABS-ECU har-
ness-side connector terminal (50)
and body earth
OK:System voltageNGCheck the following connector.
C-02NG
Repair
OK
Check trouble symptom.NGCheck the harness between the com-
bination meter and the ABS-ECU, and
repair if necessary.
OK
Check the following connector.
C-64NG
Repair
OK
Check trouble symptom.NGReplace the ABS-ECU.

ABS <2WD> ± Troubleshooting35B-21
Connector
terminal No.SignalChecking requirementsNormal condition
43Idle-up solenoid valve (±)Ignition switch: ON (The motor is on approximately
1 second after engine is started.)2 V or less
46Ignition switchIgnition switch: ONSystem voltage
Ignition switch: START0 V
47Input from diagnosis indication
selection
Connect the MUT-II.0 V
selection
Do not connect the MUT-II.Approx. 12 V
48Input from valve relay monitorIgnition switch: ONSystem voltage
49Motor monitorIgnition switch: ON
Approximately 1 second after
Motor is on.System voltage
A roximately 1 second after
engine is startedMotor is off.0.5 V or less
50Output to ABS warning lampIgnition
switch: ON
The lamp is switched off.System voltage
switch: ON
The lamp is illuminated.0 ± 2 V
52Output to front-right hydraulic
unit solenoid valve (IN side)Ignition switch: ON (When solenoid valve is off
approximately 1 second after engine is started.)System voltage

ABS <4WD> ± Troubleshooting35C-5
TROUBLESHOOTING35101110143
STANDARD FLOW OF DIAGNOSTIC TROUBLESHOOTING
Refer to GROUP 00 ± How to Use Troubleshooting/Inspection Service Points.
NOTES WITH REGARD TO DIAGNOSIS
The phenomena listed in the following table are not abnormal.
PhenomenonExplanation of phenomenon
System check soundWhen starting the engine, a thudding sound can sometimes be heard coming from inside
the engine compartment, but this is because the system operation check is being
performed, and is not an abnormality.
ABS operation sound1. Sound of the motor inside the ABS hydraulic unit operation. (whine)
2. Sound is the generated along with vibration of the brake pedal. (scraping)
3. When ABS operates, sound is generated from the vehicle chassis due to repeated
brake application and release.
(Thump: suspension; squeak: tyres)
ABS operation
(Long braking distance)For road surfaces such as snow-covered roads and gravel roads, the braking distance for
vehicles with ABS can sometimes be longer than that for other vehicles. Accordingly, advise
the customer to drive safely on such roads by lowering the vehicle speed and not being too
overconfident.
Shock during system
operation checkShock may be felt when the brake pedal is depressed slightly at a low driving speed. This
occurs due to ABS operation check (check at a vehicle speed of 8 km/h after starting), and
does not indicate any malfunction.
Diagnosis detection condition can vary depending on the diagnosis code.
Make sure that checking requirements listed in the ªCommentº are satisfied when checking the trouble
symptom again.
DIAGNOSIS FUNCTION35201120108
DIAGNOSIS CODES CHECK
Read a diagnosis code by the MUT-II or ABS warning lamp.
(Refer to GROUP 00 ± How to Use Troubleshooting/Inspection
Service Points.)
ERASING DIAGNOSIS CODES
Refer to GROUP 00 ± How to Use Troubleshooting/Inspection
Service Points.

ABS <4WD> ± Troubleshooting35C-10
Code No. 32 G-sensor systemProbable cause
This code is output at the following times:
The G-sensor output is less than 0.5 V or more than 4.5 V.
An open or short circuit is present in the G-sensor system.
Malfunction of G-sensor

Malfunction of wiring harness or connector

Malfunction of ABS-ECU
G-sensor check (Refer to P. 35C-20.)NGReplace the G-sensor.
OK
Measure at ABS-ECU connector C-62.

Ignition switch ON

Voltage between 4 and 17
OK:2.4 ± 2.6 VNGCheck the following connector.
C-02NG
Repair
OK
Check trouble symptom.NGCheck the harness between the G-sen-
sor and the ABS-ECU, and repair if nec-
essary.OK
Check the following connector.
C-62NG
Repair
OK
Check trouble symptom.
NG
Replace the ABS-ECU.
ABS WARNING LAMP INSPECTION35201200086
Refer to GROUP 35B ± Troubleshooting.
INSPECTION CHART FOR TROUBLE SYMPTOMS35201140159
Refer to GROUP 35B ± Troubleshooting.