Mitsubishi Colt Ralliart. Manual - part 232

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-20

DIAGNOSIS PROCEDURE

STEP 1. Connector check: A-06 front left wheel 
speed sensor connector

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the defective connector.

STEP 2. Remove the front left wheel speed 
sensor and check it.
Refer to 

P.35B-81

.

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Replace the front left wheel speed sensor 
(Refer to 

P.35B-80

).

STEP 3. Check the wheel bearing for excessive 
play.
Refer to GROUP 26, On-vehicle Service 

− Wheel 

Bearing Play Check 

P.26-5

.

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Replace the hub assembly (Refer to 
GROUP 26, Front Axle Hub Assembly 

P.26-6

).

STEP 4. Check the encoder for detecting wheel 
speed.
Check the encoder for presence of foreign objects or 
deformation.

Q: Is the check result normal?

YES : 

Go to Step 5.

NO : 

If foreign objects are found, clean the 
encoder. If deformation is found, replace the 
hub (Refer to GROUP 26, Front Axle Hub 
Assembly 

P.26-9

).

STEP 5. Check whether the diagnosis code is 
reset.

CAUTION

Before connecting or disconnecting the 
M.U.T.-III, turn the ignition switch to the "LOCK" 
(OFF) position.
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.

(7) Disconnect M.U.T.-III.

Q: Is code No.C1206 set?

YES : 

Replace the hydraulic unit (integrated with 

ABS-ECU) (Refer to 

P.35B-78

).

NO : 

The malfunction is intermittent. Refer to 
GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

− 

How to Cope with Intermittent Malfunction 

P.00-13

.

AC313862AE

Connector: A-06

Harness side

A-06(B)

AC206895

AC

Diagnosis

connector

MB991827

MB991824 

MB991910

Main

Index

Group

TOC

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-21

Code No.C1210: Wheel speed sensor (RR) system (open circuit, short to earth or power supply)

OPERATION

The wheel speed sensor is a pulse generator. It con-
sists of encoder (a plate on which north and south 
pole sides of the magnets are arranged alternately) 
for detecting wheel speed which rotates at the same 
speed as the road wheels. This sensor sends fre-
quency pulse signals in proportion to wheel speed.
The pulse signals, which the wheel speed sensor 
creates, are sent to the ABS-ECU. The ABS-ECU 
uses the frequency of the pulse signals to determine 
the wheel speed.

DIAGNOSIS CODE SET CONDITIONS

The ABS-ECU monitors the voltage change in each 
of the wheel speed sensor circuits. If the ECU 
detects an open or short circuit in any of the circuits, 
the ECU sets the diagnosis code.

PROBABLE CAUSES

• Damaged wiring harness or connector

• Malfunction of the wheel speed sensor

• Malfunction of the hydraulic unit (integrated with 

ABS-ECU)

FRONT WHEEL SPEED SENSOR

(LH)

(RH)

(LH)

(RH)

ABS-ECU

REAR WHEEL SPEED SENSOR

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

 Wheel Speed Sensor Circuit

Main

Index

Group

TOC

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-22

DIAGNOSIS PROCEDURE

STEP 1. Connector check: C-06 rear right wheel 
speed sensor connector

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the defective connector.

STEP 2. Remove the rear right wheel speed 
sensor and check it.
Refer to 

P.35B-81

.

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Replace the rear right wheel speed sensor 
(Refer to 

P.35B-80

).

STEP 3. Check the rear right wheel speed sensor 
connector C-06.

Check the connectors, for loose, corroded or dam-
aged terminals, or terminals pushed back in the con-
nector.

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Repair or replace the damaged 
component(s). Refer to GROUP 00, How to 
Use Troubleshooting/Inspection Service 
Points 

− Connector Inspection Service 

Points 

P.00-11

. 

STEP 4. Check the continuity (short to earth) at 
ABS-ECU connector A-05.

(1) Disconnect the rear right wheel speed sensor 

connector C-06 and ABS-ECU connector A-05, 
and connect special tool ABS Check Harness 
(MB991951) to the wiring harness-side 
connector.
NOTE: Do not connect special tool ABS Check 
Harness (MB991951) to the ABS-ECU.

AC313878

Connector: C-06

AB

Harness side

C-06(B)

AC313878

Connector: C-06

AB

Harness side

C-06(B)

AC313863AB

Connector: A-05

Harness side

A-05(B)

AC314249AB

ABS-ECU

MB991951

Check connector

A-05 Harness connector

AC313878

Connector: C-06

AB

Harness side

C-06(B)

Main

Index

Group

TOC

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-23

(2) Continuity between ABS-ECU connector A-05 

terminal 19 and body earth

OK: No continuity

(3) Continuity between ABS-ECU connector A-05 

terminal 8 and body earth

OK: No continuity

Q: Is the check result normal?

YES : 

Go to Step 5.

NO : 

Repair the wiring harness between 
ABS-ECU connector A-05 and rear right 
wheel speed sensor connector C-06.

STEP 5. Resistance measurement at ABS-ECU 
connector A-05.

(1) Disconnect the rear right wheel speed sensor 

connector C-06 and ABS-ECU connector A-05, 
and connect special tool ABS Check Harness 
(MB991951) to the wiring harness-side 
connector.
NOTE: Do not connect special tool ABS Check 
Harness (MB991951) to the ABS-ECU.

AC313972BM

Connector A-05
 (Harness side)

AC313972BN

Connector A-05
 (Harness side)

AC313863AB

Connector: A-05

Harness side

A-05(B)

AC314249AB

ABS-ECU

MB991951

Check connector

A-05 Harness connector

AC313878

Connector: C-06

AB

Harness side

C-06(B)

Main

Index

Group

TOC