Mitsubishi Grandis. Manual - part 308

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-117

Step 11. Check the wiring harness between C-208 
rear window defogger relay connector No.4 and 
G-07 rear window defogger connector No.1.

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-118

NOTE: Prior to the wiring harness inspection, check 
junction block connector C-210 and intermediate 
connector G-14, and repair if necessary.

• Check the rear window defogger relay line for 

open or short circuit.

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 : 

Repair the wiring harness.

Step 12. Connector check: G-02 rear window 
defogger connector

Q: Is the check result normal?

YES : 

Go to Step 13.

NO : 

Repair the connector.

AC310624

Connectors: C-208, C-210 <LHD>

AM

3

4

5

1

2

Junction block side

Junction block (Front view)

C-208

C-210

C-208

Harness side

C-210

AC310619

Connectors: C-208, C-210 <RHD>

AM

3

4

5

1

2

Junction block side

Junction block (Front view)

C-208

C-210

C-208

Harness side

C-210

AC310223

Connectors: G-07, G-14

AB

Harness side

G-07 (B)

G-07

G-14

G-14

2

1

4

3

13

8

11

10

5

7

12

6

14

9

AC310220

Connector: G-02

AB

Harness side

G-02 (B)

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-119

Step 13. Resistance measurement at G-02 rear 
window defogger connector.

(1) Disconnect the connector, and measure at the 

wiring harness side.

(2) Continuity between terminal 1 and body earth.

OK: 2

Ω or less

Q: Is the check result normal?

YES : 

 Go to Step 15.

NO : 

 Go to Step 14.

Step 14. Check the wiring harness between G-02 
rear window defogger connector terminal No.1 
and earth.

• Check the rear window defogger earth line for 

open or short circuit.

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 : 

Repair or replace the wiring harness.

Step 15. Check the rear window defogger.

Refer to GROUP 54A, Rear Window rear window 
defogger Switch Inspection 

P.54A-176

.

Q: Does the rear window defogger work normally? 

YES : 

The trouble can be an intermittent 

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

P.00-5

).

NO : 

Repair the rear window defogger.

INSPECTION PROCEDURE 13: The A/C indicator flashes

CIRCUIT OPERATION

If the A/C indicator flashes then the possible causes 
may be due to a defective A/C pressure system or 
insufficient refrigerant gas.

TROUBLESHOOTING HINTS

• Malfunction of the A/C pressure sensor

• Malfunction of the outside thermo sensor

• Malfunction of the A/C-ECU

Step 1. MUT-III CAN bus diagnostics

Use the MUT-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-16

.)

Step 2. MUT-III diagnosis code

Check whether the air conditioner sets a diagnosis 
code or not.

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Refer to diagnosis code chart 

P.55-8

.

Step 3. 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 4.

NO : 

Inspection Procedure 18: Refer to A/C 
pressure sensor system 

P.55-142

 <LHD> or 

Inspection Procedure 19: Refer to A/C 
pressure sensor system 

P.55-144

 <RHD>.

AC310220

Connector: G-02

AB

Harness side

G-02 (B)

AC310506

Connector G-02 
(Harness side)

AS

AC310220

Connector: G-02

AB

Harness side

G-02 (B)

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55-120

Step 4. Check the refrigerant level.

 Refer to 

P.55-193

.

Q: Is the refrigerant level correct?

YES : 

Go to Step 5.

NO : 

Correct the refrigerant level (Refer to 
On-vehicle Service 

P.55-191

.)

STEP 5. Recheck the trouble symptom

Q: Is the check result normal?

YES : 

Intermittent malfunction. (Refer to GROUP 

00 

− How to Cope with Intermittent 

Malfunction 

P.00-5

.)

NO : 

Inspection Procedure 18: Refer to A/C 
pressure sensor system 

P.55-142

 <LHD> or 

Inspection Procedure 19: Refer to A/C 
pressure sensor system 

P.55-144

 <RHD>.

INSPECTION PROCEDURE 14: Rear blower does not work <Vehicle with rear heater or rear cooler>

REAR
HEATER
CONTROLLER

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 Heater Controller Circuit <L.H.D>