Mitsubishi Outlander GS45X. Manual - part 382

ABS DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-149

SYMPTOM CHART

M1352011401582

CAUTION

• ABS may operate in the following conditions without hard braking: Slippery road surface, 

high-speed turn, and bumpy road surface. When asking the customers, confirm that they 
have/have not encountered ABS operation in corresponding conditions.

• During ABS operation, the brake pedal is pulled forward gradually, and noise occurs at the same 

time. This is because the brake line pressure varies intermittently to prevent the wheel lock, and 
not a system malfunction.

• During diagnosis, a diagnostic trouble code associated with other system may be set when the 

ignition switch is turned on with connector(s) disconnected. On completion, check all systems for 
diagnostic trouble code(s). If diagnostic trouble code(s) are set, erase them all.

Symptoms

Inspection 
procedure 
No.

Reference 
page

Scan tool cannot communicate only with ABS-ECU.

1

P.35B-150

Brake warning light stays ON with the parking brake lever released.

2

P.35B-151

ABS warning light does not illuminate when ignition switch is turned to the ON 
position (Engine stopped).

3

P.35B-157

Brake warning light does not illuminate when the ignition switch is turned to 
ON position (Engine stopped).

4

P.35B-159

ABS warning light stays ON after the engine is started.

5

P.35B-161

Abnormality in brake operation

6

P.35B-163

ABS system inoperative

7

P.35B-163

ABS-ECU power supply circuit system

8

P.35B-165

ABS operate too frequently.

9

P.35B-175

The initial check sound of hydraulic unit is loud.

10

P.35B-178

ABS DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-150

SYMPTOM PROCEDURES

Inspection Procedure 1: Scan tool cannot communicate only with ABS-ECU.

CAUTION

If there is any problem in the CAN bus lines, an incorrect 
diagnostic trouble code may be set. Prior to this diagno-
sis, diagnose the CAN bus lines (Refer to GROUP 54C 

− 

CAN Bus Line Diagnostic Flow 

P.54C-10

).

.

TECHNICAL DESCRIPTION (COMMENT)

When scan tool cannot communicate with the ABS system, the 
CAN bus line, ABS-ECU power supply circuit system, or 
ABS-ECU may be faulty.

.

TROUBLESHOOTING HINTS (THE MOST LIKELY 
CAUSES FOR THIS CASE:)

• Damaged wiring harness and connectors

• ABS-ECU malfunction

• Wrong routing of M.U.T.-III harness

• Abnormality in battery or generator

• Abnormality in power supply voltage to ABS-ECU

• ECU malfunction of other system

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, diagnose the CAN bus 
line.
Use scan tool to diagnose the CAN bus lines.
Q: Is the check result normal?

YES : Check and repair the power supply circuit system 

(Refer to 

P.35B-165

).

NO :  Repair the CAN bus lines (Refer to GROUP 54C 

− 

CAN Bus Diagnostics Table 

P.54C-10

).

ABS DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-151

Inspection Procedure 2: Brake warning light stays ON with the parking brake lever released.

Brake Warning Light Circuit

CPU

INTERFACE 
CIRCUIT

LCD

CAN 
TRANSCEIVER 
CIRCUIT

INTERFACE 
CIRCUIT

LED DRIVE 
CIRCUIT

COMBINATION 
METER

CAN DRIVE 
CIRCUIT

INTERFACE 
CIRCUIT

ETACS-
ECU

JOINT 
CONNECTOR 
(CAN1)

BRAKE 
FLUID 
LEVEL 
SWITCH

PARKING 
BRAKE 
SWITCH

FUEL WARNING/OIL 
PRESSURE WARNING

ACA02742

ABS DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-152

CAUTION

• If there is any problem in the CAN bus lines, an incor-

rect DTC may be set. Prior to this diagnosis, diagnose 
the CAN bus lines (Refer to GROUP 54C 

− CAN Bus 

Line Diagnostic Flow 

P.54C-10

).

• Whenever ECU is replaced, ensure that the CAN bus 

lines are normal.

.

OPERATION

• When the parking brake switch is turned ON, the combina-

tion meter terminal No. 4 is grounded, and then the brake 
warning light illuminates.

• When reduction of the brake fluid amount is detected, the 

brake fluid level switch is turned from ON to OFF. 
ETACS-ECU monitors the brake fluid level switch, and 
instructs the combination meter via the CAN bus line to illu-
minate the brake warning light.

.

AC901112

Connector: A-09

AM

A-09 (B)

AC901075 AC

Connector: C-03

AC901076AG

Connector: C-22

AC702828AE

Connector: C-312

AC901079

Connector: D-125

AY

D-125 (B)