Mitsubishi Grandis. Manual - part 948

TROUBLESHOOTING

TRACTION CONTROL/ACTIVE STABILITY CONTROL SYSTEM

35C-117

STEP 5. Check whether the diagnosis code is 
reset.

Check again if the diagnosis code is set.

CAUTION

To prevent damage to MUT-III, always turn the 
ignition switch to the "LOCK" (OFF) position 
before connecting or disconnecting MUT-III.
(1) Connect the MUT-III to the diagnosis connector 

as shown in the illustration.

(2) Turn the ignition switch to the "ON" position.

(3) Erase the diagnosis code (Refer to 

P.35C-6

).

(4) Turn the ignition switch to the "LOCK" (OFF) 

position.

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

position.

(8) Disconnect MUT-III.

Q: Is code No.U1120 set?

YES : 

Replace the hydraulic unit (integrated with 

TCL/ASC-ECU) (Refer to GROUP 35C - 
Hydraulic Unit 

P.35C-165

). Then go to Step 

6 .

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 6. Check whether the diagnosis code is 
reset.

Check again if the diagnosis code is set.

CAUTION

To prevent damage to MUT-III, always turn the 
ignition switch to the "LOCK" (OFF) position 
before connecting or disconnecting MUT-III.
(1) Connect the MUT-III to the diagnosis connector 

as shown in the illustration.

(2) Turn the ignition switch to the "ON" position.

(3) Erase the diagnosis code (Refer to 

P.35C-6

).

(4) Turn the ignition switch to the "LOCK" (OFF) 

position.

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

position.

(8) Disconnect MUT-III.

Q: Is code No.U1120 set?

YES : 

Return to Step 1 .

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-118

DIAGNOSTIC TROUBLE CODE 
PROCEDURES <STEERING WHEEL 
SENSOR>

Code No.C1551: Improper output voltage of steering wheel sensor
Code No.C1552: Abnormal steering wheel sensor output pattern
Code No.C1553: Abnormal optical sensor output pattern
Code No.C1554: Steering wheel sensor speed is out of range
Code No.C1555: Steering wheel sensor out of range
Code No.C1608: EEPROM failure

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.

CAUTION

If these diagnosis codes has been set, 
TCL/ASC-ECU related diagnosis code No.C1506 
is also set. After these diagnosis codes has been 
diagnosed, don’t forget to erase diagnosis code 
No.C1506.

OPERATION

• The steering wheel sensor is energized via the 

ignition switch, and communicates the 
TCL/ASC-ECU via a CAN bus-line.

• The steering wheel sensor has a self-diagnosis 

function and a memory function. If the diagnosis 
function finds a trouble, it sends these diagnosis 
codes to the TCL/ASC-ECU. Then the ECU will 
illuminate the TCL/ASC indicator light. At this 
time, the TCL/ASC-ECU sets diagnosis code 
No.C1506 (Steering wheel sensor error).

DIAGNOSIS CODE SET CONDITIONS

These diagnosis codes will be set under the cases 
below.

Code No.C1551: Improper output voltage of 

steering wheel sensor

• The Hall cell sends incorrect voltage signal for at 

least one second.

Code No.C1552: Abnormal steering wheel sensor 

output pattern

• Invalid Hall cell pattern fluctuates at least once.

Code No.C1553: Abnormal optical sensor output 

pattern

• The optical sensor output is invalid.

Code No.C1554: Steering wheel sensor speed is 

out of range

• The sensor speed is -25°/10 ms or more.

Code No.C1555: Steering wheel sensor out of 

range

• The sensor is out of a predetermined operation 

range.

Code No.C1608: EEPROM failure

• The sensor detects an EEPROM error.

PROBABLE CAUSES

Malfunction of the steering wheel sensor

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.

AC302297

AC310120

AB

MB991827

16-pin

MB991910

MB991824

TROUBLESHOOTING

TRACTION CONTROL/ACTIVE STABILITY CONTROL SYSTEM

35C-119

(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 2.

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.C1551, C1552, C1553, C1554, C1555 or 

C1608 set? 
YES : 

Replace steering wheel sensor.

NO : 

The procedure is complete.

Code No.U1073: Bus off

AC302297

AC310120

AB

MB991827

16-pin

MB991910

MB991824

TROUBLESHOOTING

TRACTION CONTROL/ACTIVE STABILITY CONTROL SYSTEM

35C-120

CAUTION

• If diagnosis code No.U1073 is set in the 

steering wheel sensor, always diagnose the 
CAN main bus line. If there is any fault in the 
CAN bus lines, an incorrect diagnosis code 
may be set.

• Whenever the ECU is replaced, ensure that 

the communication circuit is normal.

CAUTION

If diagnosis code No.U1073 has been set, 
TCL/ASC-ECU related diagnosis code No.C1506 
is also set. After diagnosis code No.U1073 has 
been diagnosed, don’t forget to erase diagnosis 
code No.C1506.

TROUBLE JUDGMENT

This code is stored when the steering wheel sensor 
has ceased the CAN communication (bus off). Then, 
if a penalty mode is entered after approximately five 
minutes, regular data transmission will be cancelled.

PROBABLE CAUSES

• 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 2.

NO : 

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

P.54D-9

). Then go to Step 3.

AC302297

AC310120

AB

MB991827

16-pin

MB991910

MB991824