Mitsubishi Colt Ralliart. Manual - part 239

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-48

Q: Is the result normal?

YES : 

Go to Step 3.

NO : 

Repair the wiring harness between the 
ABS-ECU and the battery.

STEP 3. 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.C1278 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

Main

Index

Group

TOC

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-49

Code No.C1860: ABS-ECU power supply system (abnormal voltage increase)

OPERATION

The ABS-ECU is energized by the ignition switch 
(IG1) through multi-purpose fuse 40 and the 
ABS-ECU terminal 20.

DIAGNOSIS CODE SET CONDITIONS

This diagnosis code will be set if the battery voltage 
increases to 16.9 V or more while the engine is run-
ning.

PROBABLE CAUSES

• Defective battery

• Damaged wiring harness or connector

• Malfunction of the hydraulic unit (integrated with 

ABS-ECU)

• Charging system failed

DIAGNOSIS PROCEDURE

STEP 1. Check the battery and charging system.
Check the battery and charging system.

• Ignition switch: ON

• Engine: Start

• Engine speed: Approximately 2500 rpm

Measure the voltage between the battery terminals.

OK: 16 V or less

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Inspection, repair or replace the charging 
system component(s).

STEP 2. 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.C1860 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

Main

Index

Group

TOC

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-50

Code No.C1861: ABS-ECU power supply system (abnormal voltage drop)

OPERATION

The ABS-ECU is energized by the ignition switch 
(IG1) through multi-purpose fuse 40 and the 
ABS-ECU terminal 20.

DIAGNOSIS CODE SET CONDITIONS

If the vehicle speed exceeds 6 km/h when the battery 
voltage is 7.6 V or less, the ECU will illuminate the 
charge warning light and set this diagnosis code. 
NOTE: If the battery voltage is less than 9.6 V or 9.3 
V (while the ABS is activating), the ECU will illumi-
nate the charge warning lamp, but will not set diag-
nosis code C1861. If the vehicle speed does not 
exceed 6 km/h when the battery voltage is 7.6 V or 
less, the ECU will illuminate the charge warning 
lamp, but will not set diagnosis code C1861.

PROBABLE CAUSES

• Defective battery

• Damaged wiring harness or connector

• Malfunction of the hydraulic unit (integrated with 

ABS-ECU)

• Charging system failed

IGNITION
SWITCH (IG1)

ELECTRIC
POWER
STEERING
SYSTEM

ABS-ECU

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

Power Supply Circuit

Main

Index

Group

TOC

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-51

DIAGNOSIS

STEP 1. Check the battery and charging system.
Check the battery and charging system.

• Ignition switch: ON

• Engine: Start

• Engine speed: Approximately 2500 rpm

Measure the voltage between the battery terminals.

OK: 16 V or less

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Inspection, repair or replace the charging 
system component(s).

STEP 2. Check the ACS-ECU connector A-05.

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 3.

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 3. 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: Connect special tool ABS Check Harness 
(MB991951) to the ABS-ECU.

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

AC313863AB

Connector: A-05

Harness side

A-05(B)

AC313863AB

Connector: A-05

Harness side

A-05(B)

AC601354AB

ABS-ECU

MB991951

Check connector

A-05 Harness connector

Main

Index

Group

TOC