Mitsubishi 380. Manual - part 207

AUTO A/C DIAGNOSIS

HEATER, AIR CONDITIONING AND VENTILATION

55-124

NOTE: Also check junction block connectors C-211 and C-215 
for loose, corroded, or damaged terminals, or terminals pushed 
back in the connector. If 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-16 

(terminal 28) 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.

STEP 4. Measure the voltage at A/C-ECU connector C-16. 
(1) Disconnect A/C-ECU connector C-16 and measure the 

voltage at the harness side.

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

(3) Measure the voltage between terminal 36 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 6.
NO :   Go to Step 5.

25DB096A

CONNECTORS: C-211, C-215

HARNESS SIDE

C-211

HARNESS SIDE

C-215

25DB132A

HARNESS SIDE

C-16 (B)

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22

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25

26

27

28

29

30

31

32

33

34

35

36

CONNECTOR: C-16

AC209365

21

22

23

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25

26

27

28

29

30

31

32

33

34

35

36

CONNECTOR C-16 
(HARNESS SIDE)

HL

AUTO A/C DIAGNOSIS

HEATER, AIR CONDITIONING AND VENTILATION

55-125

STEP 5. Check the wiring harness between A/C-ECU 
connector C-16 (terminal 36) and the ignition switch (ACC).

NOTE: Also check intermediate connector C-29 for loose, cor-
roded, or damaged terminals, or terminals pushed back in the 
connector. If 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-16 

(terminal 36) 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.

25DB132A

HARNESS SIDE

C-16 (B)

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

CONNECTOR: C-16

25DB133A

CONNECTORS: C-03, C-29

C-29

C-29

C-03

C-03

AUTO A/C DIAGNOSIS

HEATER, AIR CONDITIONING AND VENTILATION

55-126

STEP 6. Measure the voltage at A/C-ECU connector C-15. 
(1) Disconnect A/C-ECU connector C-16 and measure the 

voltage at the harness side.

(2) Measure the voltage between terminal 3 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.

STEP 7. Check the wiring harness between A/C-ECU 
connector C-15 (terminal 3) and the battery.

25DB120A

CONNECTOR: C-15

C-105 (B)

HARNESS SIDE

AC209365

CONNECTOR C-15 
(HARNESS SIDE)

HM

25DB120A

CONNECTOR: C-15

C-105 (B)

HARNESS SIDE

AUTO A/C DIAGNOSIS

HEATER, AIR CONDITIONING AND VENTILATION

55-127

NOTE: Also check intermediate connector C-29 for loose, cor-
roded, or damaged terminals, or terminals pushed back in the 
connector. If 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-16 

(terminal 3) and the battery 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 8. Measure the resistance at A/C-ECU connector 
C-16.
(1) Disconnect A/C-ECU connector C-16, and measure at the 

wiring harness side.

(2) Measure the resistance between terminal 27 and ground.

• The measured value should be 2 ohms or less.

Q: Does the measured resistance value correspond with 

this range?
YES : Replace the A/C-ECU, and check that the air 

conditioning works normally.

NO :   Go to Step 9.

25DB134A

CONNECTOR:  C-29

C-29

C-29

25DB132A

HARNESS SIDE

C-16 (B)

21

22

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25

26

27

28

29

30

31

32

33

34

35

36

CONNECTOR: C-16

AC209364

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23

24

25

26

27

28

29

30

31

32

33

34

35

36

CONNECTOR C-16 
(HARNESS SIDE)

JE