Mitsubishi Galant (2004+). Manual - part 775

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-239

STEP 8. Measure the voltage at defogger relay connector 
C-201. 

(1) Disconnect defogger relay connector C-201, and measure 

the voltage at the junction block side.

(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal 1 and ground.

• The measured value should be approximately 12 volts 

(battery positive voltage).

Q: Is the measured voltage approx. 12 volts?

YES :  Go to Step 10.
NO :   Go to Step 9.

STEP 9. Check the wiring harness between defogger relay 
connector C-201 (terminal 1) and ignition switch (IG2).

AC305415BE

CONNECTOR: C-201

JUNCTION BLOCK SIDE

JUNCTION BLOCK 
(FRONT VIEW)

AC209365HB

CONNECTOR C-201 
(JUNCTION BLOCK SIDE)

AC305416

CONNECTORS: C-201, C-215

JUNCTION BLOCK 
(FRONT VIEW)

HARNESS SIDE

C-201

JUNCTION BLOCK SIDE

C-201

C-215

C-215

AQ

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-240

NOTE: Also check junction block connector C-215 for loose, 
corroded, or damaged terminals, or terminals pushed back in 
the connector. If junction block connector C-215 is damaged, 
repair or replace the connector as described in GROUP 00E, 
Harness Connector Inspection 

P.00E-2

.

Q: Is the wiring harness between defogger relay connector 

C-201 (terminal 1) and ignition switch (IG2) in good 
condition?
YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

− How to 

Use Troubleshooting/Inspection Service Points 

P.00-6

.

NO :  Repair the wiring harness. Check that the defogger 

system works normally.

STEP 10. Check A/C-ECU connector C-15 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.

Q: Is A/C-ECU connector C-15 in good condition?

YES : Go to Step 11.
NO :  Repair or replace the connector. Refer to GROUP 

00E, Harness Connector Inspection 

P.00E-2

. Check 

that the defogger system works normally.

AC305233

CONNECTOR: C-15

BG

C-105 (B)

HARNESS SIDE

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-241

STEP 11. Check the wiring harness between defogger relay 
connector C-201 (terminal 3) and A/C-ECU connector C-15 
(terminal 8).
NOTE: Also check junction block connector C-211 for loose, 
corroded, or damaged terminals, or terminals pushed back in 
the connector. If junction block connector C-211 is damaged, 
repair or replace the connector as described in GROUP 00E, 
Harness Connector Inspection 

P.00E-2

.

Q: Is the wiring harness between defogger relay connector 

C-201 (terminal 3) and A/C-ECU connector C-15 
(terminal 8) in good condition?
YES : Go to Step 12.
NO :  Repair or replace the wiring harness. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-2

. Check that the defogger system works 

normally.

AC305233

CONNECTOR: C-15

BG

C-105 (B)

HARNESS SIDE

AC305416

CONNECTORS: C-201, C-211

JUNCTION BLOCK 
(FRONT VIEW)

HARNESS SIDE

C-201

JUNCTION BLOCK SIDE

C-201

C-211

C-211

AR

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-242

STEP 12. Check the wiring harness between defogger 
relay connector C-201 (terminal 4) and choke coil 
connector D-14 (terminal 1).
NOTE: Also check junction block connector C-204 for loose, 
corroded, or damaged terminals, or terminals pushed back in 
the connector. If junction block connector C-204 is damaged, 
repair or replace the connector as described in GROUP 00E, 
Harness Connector Inspection 

P.00E-2

.

Q: Is the wiring harness between defogger relay connector 

C-201 (terminal 4) and choke coil connector D-14 
(terminal 1) in good condition?
YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

P.00-6

.

NO :  Repair or replace the wiring harness. Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-2

. Check that the defogger system works 

normally.

AC305416

CONNECTORS: C-201, C-204

JUNCTION BLOCK 
(FRONT VIEW)

HARNESS SIDE

C-201

JUNCTION BLOCK SIDE

C-201

C-204

C-204

AS

AC305268

CONNECTOR: D-14

AJ

HARNESS SIDE