Mitsubishi Grandis. Manual — part 314

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-141

NOTE: Prior to the wiring harness inspection, check
intermediate connector C-128, and repair if
necessary.

• Check the input line for open circuit.

Q: Is the check result normal?

YES :

Go to Step 8.

NO :

Repair the wiring harness.

STEP 8. Recheck the trouble symptom

Q: Is the check result normal?

YES :

The trouble can be an intermittent

malfunction (Refer to GROUP 00, How to
Cope with Intermittent Malfunction

P.00-5

).

NO :

Replace the A/C-ECU.

AC310614

BC

Connectors: C-106, C-128 <LHD>

Harness side

C-106

C-128

C-106

C-128

AC310632AW

Connectors: C-106, C-128 <RHD>

Harness side

C-106

C-128

C-106

C-128

AC310649

AB

Connector: E-03 <LHD>

Harness side

AC310653

AB

Connector: E-03 <RHD>

Harness side

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-142

INSPECTION PROCEDURE 18: A/C pressure sensor system <LHD>

COMMENTS ON TROUBLE SYMPTOM

If the A/C pressure sensor is defective, the damaged
wiring harness between the A/C pressure sensor and
the A/C-ECU may be suspected.

POSSIBLE CAUSES

• Malfunction of A/C pressure sensor

• Malfunction of the A/C-ECU

• Damaged harness wires and connectors

Step 1. MUT-III data list

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

P.55-183

.)

• Item 04: Pressure sensor

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Go to Step 2.

Step 2. Connector check: A-37 A/C pressure
sensor connector

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Repair the connector.

Step 3. Inspection of A/C pressure sensor

Refer to

P.55-195

.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Replace the A/C pressure sensor.

A/C PRESSURE
SENSOR

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

A/C Pressure Sensor

AC310401

Connector: A-37 <LHD>

Harness side

AJ

A-37 (B)

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-143

Step 4. Connector check: C-106 A/C-ECU
connector

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Repair the connector.

Step 5. Check the wiring harness between A-37
A/C pressure sensor connector (terminals 2, 1
and 3) and C-106 A/C-ECU connector (terminals
25, 14 and 1).

NOTE: Prior to the wiring harness inspection, check
intermediate connector C-125 and joint connector
C-01, and repair if necessary.

• Check the input line for open circuit.

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Repair the wiring harness.

STEP 6. Recheck the trouble symptom

Q: Is the check result normal?

YES :

The trouble can be an intermittent

malfunction (Refer to GROUP 00, How to
Cope with Intermittent Malfunction

P.00-5

).

NO :

Replace the A/C-ECU.

AC310613

AB

Connector: C-106 <LHD>

Harness side

AC310401

Connector: A-37 <LHD>

Harness side

AJ

A-37 (B)

AC310614

AD

Connectors: C-01, C-106, C-125 <LHD>

C-106

C-125

C-106

Harness side

C-125

C-01

C-01

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-144

INSPECTION PROCEDURE 19: A/C pressure sensor system <RHD>

COMMENTS ON TROUBLE SYMPTOM

If the A/C pressure sensor is defective, the damaged
wiring harness between the A/C pressure sensor and
the A/C-ECU may be suspected.

POSSIBLE CAUSES

• Malfunction of A/C pressure sensor

• Malfunction of the A/C-ECU

• Damaged harness wires and connectors

Step 1. MUT-III data list

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

P.55-183

.)

• Item 04: Pressure sensor

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Go to Step 2.

Step 2. Connector check: A-37 A/C pressure
sensor connector

Q: Is the check result normal?

YES :

Go to Step 3.

NO :

Repair the connector.

Step 3. Inspection of A/C pressure sensor

Refer to

P.55-195

.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Replace the A/C pressure sensor.

A/C-ECU

IGNITION
SWITCH (IG2)

MOTOR DRIVE
CIRCUIT

OUTSIDE/INSIDE AIR
SELECTION DAMPER
CONTROL MOTOR

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

Outside/Inside Air Selection Damper Control Motor Circuit

AC310396

Connector: A-37 <RHD>

Harness side

AI

A-37 (B)