Mitsubishi Galant 9G. Manual - part 274

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-172

STEP 2. Measure the voltage at A/C-ECU connector C-10. 
(1) Disconnect A/C-ECU connector C-10 and measure the 

voltage at the harness side.

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

(3) Measure the voltage between terminal 16 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 4.
NO :   Go to Step 3.

STEP 3. Check the wiring harness between A/C-ECU 
connector C-10 (terminal 16) and the ignition switch (IG2).

AC305233AW

CONNECTOR: C-10

HARNESS SIDE

C-10 (B)

AC209365

CONNECTOR C-10 
(HARNESS SIDE)

HC

AC305233AW

CONNECTOR: C-10

HARNESS SIDE

C-10 (B)

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-173

NOTE: Also check joint connector C-03, junction block connec-
tors C-211 and C-215 for loose, corroded, or damaged termi-
nals, or terminals pushed back in the connector. If joint 
connector C-03, junction block connector C-211 or 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 A/C-ECU connector C-10 

(terminal 16) and the 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 

Cope with Intermittent Malfunctions 

P.00-14

.

NO :  Repair the wiring harness. Check that the air 

conditioning works normally.

AC305231BP

CONNECTOR: C-03

AC305416

CONNECTORS: C-211, C-215

JUNCTION BLOCK 
(FRONT VIEW)

C-215

C-211

HARNESS SIDE

C-211

HARNESS SIDE

C-215

AK

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-174

STEP 4. Measure the voltage at A/C-ECU connector C-10. 
(1) Disconnect A/C-ECU connector C-10 and measure the 

voltage at the harness side.

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

(3) Measure the voltage between terminal 7 and ground.

• The measured value should be approximately 12 volts 

(battery positive voltage).

Q: Is the measured voltage approx. 12 V?

YES :  Go to Step 6.
NO :   Go to Step 5.

STEP 5. Check the wiring harness between A/C-ECU 
connector C-10 (terminal 7) and the ignition switch (ACC).

AC305233AW

CONNECTOR: C-10

HARNESS SIDE

C-10 (B)

AC209365HD

CONNECTOR C-10 
(HARNESS SIDE)

AC305233AW

CONNECTOR: C-10

HARNESS SIDE

C-10 (B)

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-175

NOTE: Also check joint connector C-03 and intermediate con-
nector C-29 for loose, corroded, or damaged terminals, or ter-
minals pushed back in the connector. If joint connector C-03 or 
intermediate connector C-29 is damaged, repair or replace the 
connector as described in GROUP 00E, Harness Connector 
Inspection 

P.00E-2

.

Q: Is the wiring harness between A/C-ECU connector C-10 

(terminal 7) and the ignition switch (ACC) 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 

Cope with Intermittent Malfunctions 

P.00-14

.

NO :  Repair the wiring harness. Check that the air 

conditioning works normally.

STEP 6. Measure the voltage at A/C-ECU connector C-10. 
(1) Disconnect A/C-ECU connector C-10 and measure the 

voltage at the harness side.

(2) Measure the voltage between terminal 8 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 8.
NO :   Go to Step 7.

AC305232

CONNECTORS: C-03, C-29

C-29

C-29

C-03

C-03

AT

AC305233AW

CONNECTOR: C-10

HARNESS SIDE

C-10 (B)

AC209365

CONNECTOR C-10 
(HARNESS SIDE)

HE