Mitsubishi Grandis. Manual - part 929

TROUBLESHOOTING

TRACTION CONTROL/ACTIVE STABILITY CONTROL SYSTEM

35C-41

STEP 8. 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) Drive the vehicle at 20 km/h or more for 30 

seconds or   more.

(6) Check if the diagnosis code is set.
(7) Turn the ignition switch to the "LOCK" (OFF) 

position.

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

C1251, C1256, C1261, C1300, C1305, C1310 or 
C1315 set?

YES : 

Go to Step 1.

NO : 

The procedure is complete.

AC302297

AC310120

AB

MB991827

16-pin

MB991910

MB991824

TROUBLESHOOTING

TRACTION CONTROL/ACTIVE STABILITY CONTROL SYSTEM

35C-42

Code No. C1271: Motor drive circuit (Abnormal power supply voltage)

CAUTION

If there is any problem in the CAN bus lines, an 
incorrect diagnosis code may be set. Diagnose 
the CAN bus lines before the Diagnosis codes 
(Refer to GROUP 54D, CAN bus-line diagnostic 
flow 

P.54D-9

).

OPERATION

• The TCL/ASC-ECU contains the power supply 

circuit (terminal 1) for the pump motor. The pump 
motor is energized by the motor switch, which is 
incorporated in the TCL/ASC-ECU.

• The pump motor switch, which is incorporated in 

the TCL/ASC-ECU, is always off unless the motor 
solenoid valve check is activated when the 
vehicle is started.

• The TCL/ASC-ECU activates the pump motor by 

turning on the ECU built-in pump motor switch 
when the ABS is working.

DIAGNOSIS CODE SET CONDITIONS

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

• This code is set if the pump motor power supply 

voltage is abnormally low for long time when the 
pump motor does not operate.

AC313584

3

FUSIBLE 
LINK

FUSIBLE 
LINK

HYDRAULIC UNIT

SOLENOID VALVE

SOLENOID 
VALVE POWER 
SOURCE

MOTOR 
POWER SOURCE

SOLENOID
VALVE 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   

4

TCL/ASC-ECU

Solenoid Valve and Motor Power Supply Circuit

AB

TROUBLESHOOTING

TRACTION CONTROL/ACTIVE STABILITY CONTROL SYSTEM

35C-43

• This code is set if the pump motor voltage is 

abnormally high for long time when the pump 
motor does not operate.

• This code is set if the pump motor switch voltage 

drop indicates high value when the pump motor 
operates.

• If code No.C1860 or C1861 is not set and the 

pump motor power supply voltage is not normal 
when the pump motor operates, the ECU 
determines that the pump motor is defective, and 
sets this diagnosis code.

PROBABLE CAUSES

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

• Malfunction of the pump motor

• Damaged wiring harness or connector

• Malfunction of the hydraulic unit (integrated with 

TCL/ASC-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 normal?

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.

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.C1271 set?

YES : 

Go to Step 3.

NO : 

The procedure is complete.

AC302297

AC310120

AB

MB991827

16-pin

MB991910

MB991824

AC302297

AC310120

AB

MB991827

16-pin

MB991910

MB991824

TROUBLESHOOTING

TRACTION CONTROL/ACTIVE STABILITY CONTROL SYSTEM

35C-44

STEP 3. Voltage measurement at TCL/ASC-ECU 
connector A-04.

(1) Disconnect the connector A-04, and connect 

special tool ABS Check Harness (MB991997) to 
the wiring harness-side connector.
NOTE: Do not connect special tool ABS Check 
Harness (MB991997) to the TCL/ASC-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.

STEP 4. Check TCL/ASC-ECU connector A-04 for 
loose, corroded or damaged terminals, or 
terminals pushed back in the connector.

Q: Is the check result normal?

YES : 

An open or short circuit may be present in 

the solenoid valve power supply circuit. 
Repair the wiring harness between 
TCL/ASC-ECU connector A-04 terminal 1 
and fusible link No.4. Then go to Step 8.

NO : 

Repair or replace the damaged 
component(s). Then go to Step 8.

AC312620AN

Oil reservoir

Connector: A-04

TCL/ASC-ECU

MB991997

Check connector

A-04 Harness connector

A-04

Hydraulic unit
(with built-in TCL/ASC-ECU)

AC312621

Oil reservoir

Connector: A-04

AB

A-04

Hydraulic unit
(with built-in TCL/ASC-ECU)

A-04 Harness connector
(harness side)