Mitsubishi Colt Ralliart. Manual — part 631

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-69

Code No. C1555: Steering wheel sensor exceeding the normal range

OPERATION

The steering wheel sensor output signal is sent to
ASC-ECU via the dedicated CAN bus lines.

DIAGNOSIS CODE SET CONDITIONS

When an abnormality (larger than the actual maxi-
mum steering angle) is detected in the steering
angle, the diagnosis is set.

PROBABLE CAUSES

• Steering wheel sensor malfunction

• Steering wheel sensor improper installation

• Steering wheel sensor calibration error

• ASC-ECU malfunction

DIAGNOSTIC PROCEDURE

STEP 1. M.U.T.-III data list
With the front wheel facing in the straight-ahead
direction, check the steering wheel sensor signal
using the data list. Check that the data list shows the
deviation within

±5° from the neutral position.(Refer

to

P.35C-109

.)

• Item No. 16: Steering angle sensor

Q: Is the check result normal?

YES :

Go to Step 2.

NO :

Perform calibration of steering wheel
sensor.(Refer to

P.35C-119

.)

STEP 2. Steering wheel sensor installation state
check
Check that the steering wheel sensor is installed cor-
rectly.

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Install the steering wheel sensor correctly.

STEP 3. M.U.T.-III data list
Turn the steering wheel fully to the left, and then turn
it fully to the right. Then check that the value of the
steering wheel sensor changes smoothly using the
data list. In addition, check that the steering wheel
angle on the data list almost matches the actual
steering wheel angle.(Refer to

P.35C-109

.)

• Item No. 16: Steering angle sensor

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

After the steering wheel is replaced, perform
the steering wheel sensor calibration.(Refer
to

P.35C-119

.)

STEP 4. Diagnosis code recheck
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition switch: LOCK (OFF) position
(3) Ignition switch: ON

Q: Is diagnosis code No. C1505 set?

YES :

Replace the ASC-ECU.

NO :

Intermittent malfunction (Refer to GROUP
00

− How to Cope with Intermittent

Malfunction

P.00-13

.)

Code No. C1607: Malfunction of ASC-ECU

CAUTION

If there is any problem in the CAN bus lines, an
incorrect diagnosis code may be set. Prior to this
diagnosis, always diagnose the CAN bus lines.

DIAGNOSIS CODE SET CONDITIONS

When an abnormality is present in the internal
ASC-ECU, this diagnosis code is set.

PROBABLE CAUSES

ASC-ECU malfunction

DIAGNOSTIC PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES :

Go to Step 2.

NO :

Repair the CAN bus lines. (Refer to GROUP
54D

− Troubleshooting

P.54D-13

.) On

completion, go to Step 2.

Main

Index

Group

TOC

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-70

STEP 2. Diagnosis code recheck
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition switch: LOCK (OFF) position

(3) Ignition switch: ON

Q: Is the diagnosis code No. C1607 set?

YES :

Replace the ASC-ECU.

NO :

This diagnosis is complete.

Code No. C1621: G and yaw rate sensor improper installation

CAUTION

If there is any problem in the CAN bus lines, an
incorrect diagnosis code may be set. Prior to this
diagnosis, always diagnose the CAN bus lines.

OPERATION

ASC-ECU automatically recognises the type of G
and yaw rate sensor via the CAN bus lines. If another
type of G and yaw rate sensor is installed after auto-
matic recognition, this code is stored.

DIAGNOSIS CODE SET CONDITIONS

If an abnormality is judged to have occurred in the G
and yaw rate sensor, the G and yaw rate sensor
sends a diagnostic signal to ASC-ECU. When
ASC-ECU receives this diagnostic signal, it deter-
mines that the sensor has a trouble and sets the
diagnosis code.

Current trouble

• Another type G and yaw rate sensor installation

• ASC-ECU malfunction

DIAGNOSTIC PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Repair the CAN bus lines. (Refer to GROUP
54D

− Troubleshooting

P.54D-13

.) On

completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting
CAN bus lines

Q: Is the diagnosis code No. C1621 set?

YES :

Go to Step 3.

NO :

This diagnosis is complete.

STEP 3. Diagnosis code recheck
Check if the diagnosis code No. C1621 is set as a
past trouble.

Q: Is the trouble set as a past trouble?

YES :

Erase the diagnosis code No. C1621.

NO :

Go to Step 4.

STEP 4. Diagnosis code recheck after sensor ID
erase execution
(1) Erase the sensor ID.
(2) Ignition switch: LOCK (OFF) position
(3) Ignition switch: ON
(4) Erase the diagnosis code.

Q: Is the diagnosis code No. C1621 set?

YES :

Replace the G and yaw rate sensor, and

then go to Step 5.

NO :

This diagnosis is complete.

STEP 5. Diagnosis code recheck after sensor ID
erase execution
(1) Erase the sensor ID.
(2) Ignition switch: LOCK (OFF) position
(3) Ignition switch: ON
(4) Erase the diagnosis code.

Q: Is the diagnosis code No. C1621 set?

YES :

Replace the ASC-ECU, and then go to Step

6.

NO :

This diagnosis is complete.

STEP 6. Diagnosis code recheck
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition switch: LOCK (OFF) position
(3) Ignition switch: ON

Q: Is the diagnosis code No. C1621 set?

YES :

Return to Step 1.

NO :

This diagnosis is complete.

Main

Index

Group

TOC

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-71

Code No. C1860: Abnormal rise of ASC-ECU power supply voltage

CAUTION

If there is any problem in the CAN bus lines, an
incorrect diagnosis code may be set. Prior to this
diagnosis, always diagnose the CAN bus lines.

DIAGNOSIS CODE SET CONDITIONS

ASC-ECU monitors the ASC-ECU power supply volt-
age sent from the battery. When the voltage rises up
to approximately 17 V or more, the ECU determines
that the trouble occurs and sets the diagnosis code.

Current trouble

• Charging circuit failure

• ASC-ECU malfunction

DIAGNOSTIC PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Repair the CAN bus lines. (Refer to GROUP
54D

− Troubleshooting

P.54D-13

.) On

completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting
CAN bus lines

Q: Is the diagnosis code No. C1860 set?

YES :

Go to Step 3.

NO :

This diagnosis is complete.

STEP 3. Battery terminal voltage measurement
(1) Start the engine.
(2) Set the engine speed to approximately 2500 rpm.
(3) Measure the voltage between the positive and

negative battery terminals.

OK: 16 V or less

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Diagnose the charging system. (Refer to
GROUP 16

− On-vehicle Service

P.16-6

.)

STEP 4. Diagnosis code recheck
(1) Start the engine.
(2) Set the engine speed to approximately 2500 rpm.

Q: Is the diagnosis code No. C1860 set?

YES :

Replace the ASC-ECU.

NO :

Intermittent malfunction (Refer to GROUP
00

− How to Cope with Intermittent

Malfunction

P.00-13

.)

Main

Index

Group

TOC

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-72

Code No. C1861: Abnormal drop of ASC-ECU power supply voltage

CAUTION

If there is any problem in the CAN bus lines, an
incorrect diagnosis code may be set. Prior to this
diagnosis, always diagnose the CAN bus lines.

DIAGNOSIS CODE SET CONDITIONS

ASC-ECU monitors the ASC-ECU power supply volt-
age sent from the battery. When the voltage is
approximately 8 V or less at the vehicle speed of 6
km/h, the ECU determines that the trouble occurs
and sets the diagnosis code.

Current trouble

• Damaged wiring harness and connectors

• Charging circuit failure

• ASC-ECU malfunction

DIAGNOSTIC PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Repair the CAN bus lines. (Refer to GROUP
54D

− Troubleshooting

P.54D-13

.) On

completion, go to Step 2.

Hydraulic unit (Motor and Solenoid Valve) Circuit

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

FUSIBLE
LINK

FUSIBLE
LINK

3

5

ASC-ECU

HYDRAULIC UNIT

SOLENOID
VALVE
POWER
SOURCE

ABS SOLENOID VALVE

MOTOR

MOTOR
POWER
SOURCE

Main

Index

Group

TOC