Mitsubishi Colt Ralliart. Manual - part 445

TROUBLESHOOTING

POWER STEERING

37-47

STEP 5. Check whether the diagnosis code is 
reset.

AC206895

AC

Diagnosis

connector

MB991827

MB991824 

MB991910

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) Start the engine.
(6) Check if the diagnosis code is set.
(7) Turn the ignition switch to the "LOCK" (OFF) 

position.

(8) Disconnect M.U.T.-III.

Q: Is diagnosis code C1542 set?

YES : 

Replace the electric power steering-ECU 

(Refer to 

P.37-102

). 

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

.

Main

Index

Group

TOC

TROUBLESHOOTING

POWER STEERING

37-48

Code No.C1860 Power supply voltage abnormality (high voltage)

CAUTION

• If the electric power steering-ECU sets diagnosis code No.C1860, diagnose the CAN bus lines. If 

there is any fault in the CAN bus lines, an incorrect diagnosis code may be set.

•

Power Supply and Earth Circuit

FUSIBLE
LINK

IGNITION
SWITCH (IG1)

4

ABS

ELECTRIC POWER
STEERING-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 : Grey     R : Red     P : Pink     V : Violet     PU : Purple

Whenever the ECU is replaced, ensure that the communication circuit is normal.

DIAGNOSIS CODE SET CONDITIONS

• The power supply voltage is more than a prede-

termined voltage stored in the microcomputer, 
and the microcomputer determines that there is a 
problem in the power supply system.
Criteria for judging malfunction

• Power supply voltage is more than 17.22 V

PROBABLE CAUSES

• Defective battery

• Charging system failed

• Malfunction of the electric power steering-ECU

DIAGNOSTIC PROCEDURE

STEP 1. Check the battery voltage.
Start the engine and measure the battery voltage.

Q: Does the voltage measure 16 V or less?

YES : 

Go to Step 2.

NO : 

Check the charging system and repair if 
necessary (Refer to GROUP 16, On-vehicle 
Service 

− Regulated Voltage Test 

P.16-9

).

Main

Index

Group

TOC

TROUBLESHOOTING

POWER STEERING

37-49

STEP 2. Check whether the diagnosis code is 
reset.

AC206895

AC

Diagnosis

connector

MB991827

MB991824 

MB991910

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) Start the engine, and check the diagnosis code.
(6) Turn the ignition switch to the "LOCK" (OFF) 

position.

(7) Disconnect M.U.T.-III.

Q: Is diagnosis code C1860 set?

YES : 

Replace the electric power steering-ECU 

(Refer to 

P.37-102

). 

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

.

Main

Index

Group

TOC

TROUBLESHOOTING

POWER STEERING

37-50

Code No.C1861 Power supply voltage abnormality (low voltage)

CAUTION

• If the electric power steering-ECU sets diagnosis code No.C1861, diagnose the CAN bus lines. If 

there is any fault in the CAN bus lines, an incorrect diagnosis code may be set.

•

Power Supply and Earth Circuit

FUSIBLE
LINK

IGNITION
SWITCH (IG1)

4

ABS

ELECTRIC POWER
STEERING-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 : Grey     R : Red     P : Pink     V : Violet     PU : Purple

Whenever the ECU is replaced, ensure that the communication circuit is normal.

DIAGNOSIS CODE SET CONDITIONS

• The power supply voltage is less than a predeter-

mined voltage stored in the microcomputer, and 
the microcomputer determines that there is a 
problem in the power supply system.
Criteria for judging malfunction

• Power supply voltage is less than 9 V

PROBABLE CAUSES

• Defective battery

• Charging system failed

• Malfunction of the electric power steering-ECU

• Damaged harness wires and connectors

DIAGNOSTIC PROCEDURE

STEP 1. Check the battery voltage.
Start the engine and measure the battery voltage.

Q: Does the voltage measure 10 V or more?

YES : 

Go to Step 2.

NO : 

Check the battery and the charging system 
and repair if necessary (Refer to GROUP 
54A, Battery 

− Battery Test 

P.54A-5

 or 

GROUP 16, On-vehicle Service 

− 

Regulated Voltage Test 

P.16-9

).

Main

Index

Group

TOC