Mitsubishi Grandis. Manual — part 905

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-35

YES :

Replace the hydraulic unit (integrated with

ABS-ECU). Then go to Step 15.

NO :

It can be assumed that this malfunction is
intermittent. Refer to GROUP 00, How to
Use Troubleshooting/Inspection Service
Points

− How to Cope with Intermittent

Malfunction

P.00-5

.

STEP 15. Check whether the diagnosis code is
reset.

Check again if the diagnosis code is set.
(1) Turn the ignition switch to the "ON" position.

(2) Erase the diagnosis code.
(3) Turn the ignition switch to the "LOCK" (OFF)

position.

(4) Turn the ignition switch to the "ON" position.
(5) Check if the diagnosis code is set.
(6) Turn the ignition switch to the "LOCK" (OFF)

position.

Q: Is code No.C1201, C1206, C1211 or C1216 set?

YES :

Go to Step 1.

NO :

The procedure is complete.

AC302297

AC310120

AB

MB991827

16-pin

MB991910

MB991824

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-36

Code No.C1226: Control solenoid valve (FR) pressure holding system
Code No.C1236: Control solenoid valve (FL) pressure holding system
Code No.C1246: Control solenoid valve (RR) pressure holding system
Code No.C1256: Control solenoid valve (RL) pressure holding system
Code No.C1231: Control solenoid valve (FR) decompressing system
Code No.C1241: Control solenoid valve (FL) pressure reducing system
Code No.C1251: Control solenoid valve (RR) pressure reducing system
Code No.C1261: Control solenoid valve (RL) decompressing system

CAUTION

If there is any problem in the CAN bus lines, an
incorrect diagnosis code may be set. Prior to this
diagnosis, diagnose the CAN bus lines.

OPERATION

• The ABS-ECU contains the power supply circuit

(terminal 1) for the solenoid valve. The solenoid
valve is energized by the valve relay, which is

incorporated in the ABS-ECU.

• The valve relay, which is incorporated in the

ABS-ECU, is always energizing the solenoid
valve unless the initial check is in progress when
the ignition switch is turned on.

• The ABS-ECU activates the solenoid valve by

turning on its driving transistor.

3

FUSIBLE
LINK

4

FUSIBLE
LINK

ABS-ECU

SOLENOID
VALVE POWER
SOURCE

SOLENOID
VALVE POWER
SOURCE

SOLENOID VALVE

HYDRAULIC UNIT

MOTOR
POWER
SOURCE

MOTOR
POWER
SOURCE

Wire colour code
B : Black LG : Light green G : Green L : Blue
W : White Y : Yellow SB : Sky blue BR : Brown
O : Orange GR : Gray R : Red P : Pink V : Violet

Solenoid Valve and Motor Power Supply Circuit

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-37

DIAGNOSIS CODE SET CONDITIONS

These diagnosis codes will be set under the cases
below.

• The solenoid valve is not energized even after

the ABS-ECU has turned on the driving transistor
(Open circuit is present in the power supply
circuit to the ABS-ECU solenoid valve, or the
valve relay has failed).

• The solenoid valve is not energized even after

the ABS-ECU has turned on the driving transistor
(Open circuit is present in the solenoid valve
circuit inside the ABS-ECU, or the valve relay has
failed).

• After the ABS-ECU has turned off the driving

transistor, the solenoid valve still remains
energized (short in the solenoid valve circuit).

• When a solenoid valve failure is detected

PROBABLE CAUSES

The most likely causes for these diagnosis codes to
set are:

• Damaged wiring harness or connector

• Malfunction of the hydraulic unit (integrated with

ABS-ECU)

DIAGNOSIS

STEP 1. MUT-III CAN bus diagnostics.

CAUTION

Before connecting or disconnecting the MUT-III,
turn the ignition switch to the "LOCK" (OFF)
position.
(1) Connect MUT-III to the 16-pin diagnosis

connector.

(2) Turn the ignition switch to the "ON" position.
(3) Diagnose the CAN bus line.
(4) Turn the ignition switch to the "LOCK" (OFF)

position.

Q: Is the check result?

YES :

Go to Step 3.

NO :

Repair the CAN bus line (Refer to GROUP
54D, CAN bus line Diagnostic flow

P.54D-9

). Then go to Step 2.

AC302297

AC310120

AB

MB991827

16-pin

MB991910

MB991824

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-38

STEP 2. Check whether the diagnosis code is
reset.

CAUTION

Before connecting or disconnecting the MUT-III,
turn the ignition switch to the "LOCK" (OFF)
position.
(1) Turn the ignition switch to the "ON" position.
(2) Erase the diagnosis code.
(3) Turn the ignition switch to the "LOCK" (OFF)

position.

(4) Turn the ignition switch to the "ON" position.
(5) Check if the diagnosis code is set.
(6) Turn the ignition switch to the "LOCK" (OFF)

position.

Q: Is code No.C1226, C1231, C1236, C1241, C1246,

C1251, C1256 or C1261 set?

YES :

Go to Step 3.

NO :

The procedure is complete.

STEP 3. Voltage measurement at ABS-ECU
connector A-03.

(1) Disconnect the connector A-03, and connect

special tool ABS Check Harness (MB991974) to
the wiring harness-side connector.
NOTE: Do not connect special tool ABS Check
Harness (MB991974) to the ABS-ECU.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 1 and

earth.

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Go to Step 4.

AC302297

AC310120

AB

MB991827

16-pin

MB991910

MB991824

AC312620AG

Oil reservoir

Connector: A-03

ABS-ECU

MB991974

Check connector

A-03 Harness connector

A-03

Hydraulic unit
(with built-in ABS-ECU)