Mitsubishi Colt Ralliart. Manual - part 236

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-36

STEP 4. Resistance measurement at ABS-ECU 
connector A-05.

(1) Disconnect the 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.

(2) Measure the resistance between terminal 23 and 

earth.

OK: 5 

Ω or less

Q: Is the result normal?

YES : 

Go to Step 6.

NO : 

Go to Step 5.

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

(1) Disconnect the 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.

(2) Measure the resistance between terminal 26 and 

earth.

OK: 5 

Ω or less

Q: Is the result normal?

YES : 

Go to Step 6.

NO : 

Repair the wiring harness between the 
ABS-ECU and body earth.

AC313863AB

Connector: A-05

Harness side

A-05(B)

AC314249AB

ABS-ECU

MB991951

Check connector

A-05 Harness connector

AC313972BH

Check connector
 (Harness side)

AC313863AB

Connector: A-05

Harness side

A-05(B)

AC313972BB

1

2

3

4

5

7

8

9

10

11

18

19

20

21

22

13

14

15

16

17

6

12

23

24

25

26

Check connector
 (Harness side)

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Index

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TOC

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-37

STEP 6. 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.
(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.C1266 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

.

AC206895

AC

Diagnosis

connector

MB991827

MB991824 

MB991910

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Index

Group

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TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-38

Code No.C1273: Motor relay stuck off

OPERATION

• The ABS-ECU contains the power supply circuit 

(terminal No.25) for the motor pump. The motor 
pump is energised by the pump relay, which is 
incorporated in the ABS-ECU.

• The pump relay, which is incorporated in the 

ABS-ECU, is always energising the motor pump 
unless the initial check is in progress when the 
ignition switch is turned on, or the recurrent sys-
tem check is in progress.

DIAGNOSIS CODE SET CONDITIONS

These diagnosis codes will be set under the cases 
below.

• If the voltage, which is created by the pump 

motor, is abnormal after the motor relay is turned 
on, the ECU determines that the motor relay is 
stuck off, and sets this diagnosis code.

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)

ABS-ECU

SOLENOID
VALVE POWER
SOURCE

MOTOR POWER SOURCE

MOTOR

SOLENOID VALVE

HYDRAULIC UNIT

FUSIBLE
LINK

FUSIBLE
LINK

CHARGING
SYSTEM

3

5

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

Hydraulic Unit (Motor and Solenoid Valve) Circuit

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TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-39

DIAGNOSIS PROCEDURE

STEP 1. Check ABS-ECU connector A-05 for 
loose, corroded or damaged terminals, or 
terminals pushed back in the connector.

Q: Is the check result normal?

YES : 

Go to Step 2.

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 2. Voltage measurement at ABS-ECU 
connector A-05.

(1) Disconnect the 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.

(2) Measure the voltage between terminal 25 and 

earth.

OK: System voltage

AC313863AB

Connector: A-05

Harness side

A-05(B)

AC313863AB

Connector: A-05

Harness side

A-05(B)

AC314249AB

ABS-ECU

MB991951

Check connector

A-05 Harness connector

AC313972 BS

Check connector 
(Harness side)

Main

Index

Group

TOC