Mitsubishi Grandis. Manual — part 286

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-29

Code No.B1055 Motor drive system for rear air mix damper <vehicles with dual automatic A/C>

COMMENTS ON TROUBLE SYMPTOM

This code is set when the rear air mixing damper
cannot be rotated to the preset opening angle.

POSSIBLE CAUSES

• Malfunction of the rear air mixing damper control

motor and potentiometer

• Malfunction of the automatic air conditioner

control panel (A/C-ECU)

• Damaged the wiring harness or connectors

DIAGNOSIS

Step 1. MUT-III actuator test

Check that the following actuator test can be
executed normally.

• Item 13: R.Air mix dumper motor: 0%

• Item 14: R.Air mix dumper motor: 50%

• Item 15: R.Air mix dumper motor: 100%

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Go to Step 2.

REAR 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

Rear Air Mixing Damper Control Motor And Potentiometer Circuit

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-30

Step 2. Connector check: C-105 A/C-ECU
connector and G-13-1 rear air mixing damper
control motor and potentiometer connector

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Repair the connector.

AC310613

AC

Connector: C-105 <LHD>

Harness side

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

AC310631AC

Connector: C-105 <RHD>

Harness side

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

AC311184

Connector: G-13-1

AB

Harness side

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-31

Step 3. Check the wiring harness between C-105
A/C-ECU connector (terminals 35 and 36) and
G-13-1 rear air mixing damper control motor and
potentiometer connector (terminals 2 and 1).

NOTE:

Prior to the wiring harness inspection, check
intermediate connector C-15 and G-13, and repair if
necessary.

• Check the motor activating lines 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 rear air mixing damper control
motor and potentiometer.

Refer to

P.55-216

.

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Replace the 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

.)

AC310613

AC

Connector: C-105 <LHD>

Harness side

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

AC310631AC

Connector: C-105 <RHD>

Harness side

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

AC311184

Connector: G-13, G-13-1

AD

Harness side

G-13-1

G-13

G-13-1

G-13

AC310615

AD

Connector: C-15 <LHD>

AC310628AE

Connector: C-15 <RHD>

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-32

Code No. B1061,B1062: Potentiometer system for air outlet changeover damper <LHD>

COMMENTS ON TROUBLE SYMPTOM

This code is set when the mode selection 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 mode selection 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 14: F.Air outlet c/o potentiometer

• Item 15: F.Air outlet c/o potentiometer (Target)

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Go to Step 2.

Step 2. Connector check: C-106 A/C-ECU
connector and C-04 mode selection damper
control motor and potentiometer connector

Q: Is the check result normal?

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

A/C-ECU

MODE SELECTION
DAMPER CONTROL
MOTOR AND
POTENTIOMETER

Mode Selection Damper Control Motor And Potentiometer Circuit

AC310614

AH

Connectors: C-04, C-106 <LHD>

Harness side

C-106

C-04

C-106

Harness side

C-04 (GR)