Mitsubishi Grandis. Manual — part 283

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-17

Step 4. Check the air thermo sensor.

Refer to

P.55-205

.

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Replace the air thermo sensor.

Step 5. MUT-III diagnosis code

Q: Is the diagnosis code set?

YES :

Replace the automatic air conditioner

control panel (A/C-ECU)

NO :

The trouble can be an intermittent
malfunction (Refer to GROUP 00, How to
Cope with Intermittent Malfunction

P.00-5

.)

Code No. B1041,B1042: Potentiometer system for the front air mix damper <LHD>

COMMENTS ON TROUBLE SYMPTOM

This code is set when the air mixing damper control
motor potentiometer does not send any signal to the
A/C-ECU due to short or open circuit.

POSSIBLE CAUSES

• Malfunction of the front air mixing damper control

motor and potentiometer

• Damaged the wiring harness or connectors

• Malfunction of the automatic air conditioner

control panel (A/C-ECU)

DIAGNOSIS

Step 1. MUT-III data list

Check that the following service data display
contents are normal. (Refer to

P.55-183

.)

• Item 10: F.Air mix potentiometer

• Item 11: F.Air mix potentiometer (Target)

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Go to Step 2.

FRONT AIR MIXING DAMPER
CONTROL MOTOR AND
POTENTIOMETER

A/C-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

Front Air Mixing Damper Control Motor And Potentiometer Circuit

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-18

Step 2. Connector check: C-106 A/C-ECU
connector and C-11 front air mixing damper
control motor and potentiometer connector

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Repair the connector.

Step 3. Check the wiring harness between C-106
A/C-ECU connector (terminals 1, 14 and 20) and
C-11 front air mixing damper control motor and
potentiometer connector (terminals 7, 5 and 3).

NOTE: Prior to the wiring harness inspection, check
joint connector C-01, and repair if necessary.

• Check the potentiometer power supply, earth and

signal line for open or short circuit.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the wiring harness.

Step 4. Check the front air mixing damper control
motor and potentiometer.

Refer to

P.55-208

.

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Replace the front air mixing damper control
motor and potentiometer.

AC310615

Connector: C-11 <LHD>

AC

Harness side

AC310613

AB

Connector: C-106 <LHD>

Harness side

AC310614

AG

Connectors: C-01, C-106 <LHD>

C-01

C-106

C-01

C-106

Harness side

AC310615

Connector: C-11 <LHD>

AC

Harness side

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-19

Step 5. MUT-III diagnosis code

Q: Is the diagnosis code set?

YES :

Replace the automatic air conditioner

control panel (A/C-ECU)

NO :

The trouble can be an intermittent
malfunction (Refer to GROUP 00, How to
Cope with Intermittent Malfunction

P.00-5

.)

Code No. B1041,B1042: Potentiometer system for the air mix damper <RHD>

COMMENTS ON TROUBLE SYMPTOM

This code is set when the front air mixing damper
control motor potentiometer does not send any
signal to the A/C-ECU due to short or open circuit.

POSSIBLE CAUSES

• Malfunction of the front air mixing damper control

motor and potentiometer

• Damaged the wiring harness or connectors

• Malfunction of the automatic air conditioner

control panel (A/C-ECU)

DIAGNOSIS

Step 1. MUT-III data list

Check that the following service data display
contents are normal. (Refer to

P.55-183

.)

• Item 10: F.Air mix potentiometer

• Item 11: F.Air mix potentiometer (Target)

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Go to Step 2.

A/C-ECU

FRONT AIR MIXING DAMPER
CONTROL MOTOR AND
POTENTIOMETER

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

Front Air Mixing Damper Control Motor And Potentiometer Circuit

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-20

Step 2. Connector check: C-106 A/C-ECU
connector and C-11 front air mixing damper
control motor and potentiometer connector

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Repair the connector.

Step 3. Check the wiring harness between C-106
A/C-ECU connector (terminals 14, 20 and 1) and
C-11 front air mixing damper control motor and
potentiometer connector (terminals 5, 3 and 7).

• Check the potentiometer power supply, earth and

signal line for open or short circuit.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the wiring harness.

Step 4. Check the front air mixing damper control
motor and potentiometer.

Refer to

P.55-208

.

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Replace the front air mixing damper control
motor and potentiometer.

Step 5. MUT-III diagnosis code

Q: Is the diagnosis code set?

YES :

Replace the automatic air conditioner

control panel (A/C-ECU)

NO :

The trouble can be an intermittent
malfunction (Refer to GROUP 00, How to
Cope with Intermittent Malfunction

P.00-5

.)

AC310628

Connector: C-11 <RHD>

AD

Harness side

AC310631AB

Connectors: C-106 <RHD>

Harness side

AC310628

Connector: C-11 <RHD>

AD

Harness side

AC310631AB

Connectors: C-106 <RHD>

Harness side