Mitsubishi Outlander GS45X. Manual - part 1014

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-83

.

CIRCUIT OPERATION

If the blower motor speed cannot be changed, the 
power transistor circuit is suspected.

.

TROUBLESHOOTING HINTS

• Malfunction of the power transistor

• Malfunction of the A/C-ECU

• Damaged harness wires or connectors

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB992006: Extra Fine Probe

STEP 1. Check power transistor connector C-120 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.
Q: Is power transistor connector C-120 in good condition?

YES : Go to Step 2.
NO :  Repair or replace the connector. Refer to GROUP 

00E, Harness Connector Inspection 

P.00E-2

.The 

blower motor should operate normally.

STEP 2. Measure the resistance at power transistor 
connector C-120.
(1) Disconnect power transistor connector C-120, and measure 

the resistance at the wiring harness side.

(2) Measure the resistance value between terminal 1 and 

ground.

OK: The measured value should be 2 ohms or less

Q: Does the measured resistance value correspond with 

this range?
YES :  Go to Step 4.
NO :   Go to Step 3.

AC702208AJ

Connector: C-109, C-120

C-120

C-109 (B)

AC608812EG

Harness side: C-120

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-84

STEP 3. Check the wiring harness between power 
transistor connector C-120 (terminal 1) and ground.

• Check the power transistor ground line for open circuit.

Q: Is the wiring harness between power transistor 

connector C-120 (terminal 1) and ground 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.00-15

.

NO :  Repair the wiring harness. The blower motor should 

operate normally.

STEP 4. Check A/C-ECU connector C-109 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.
Q: Is A/C-ECU connector C-109 in good condition?

YES : Go to Step 5.
NO :  Repair or replace the connector. Refer to GROUP 

00E, Harness Connector Inspection 

P.00E-2

.The 

blower motor should operate normally.

STEP 5. Check the wiring harness between A/C-ECU 
connector C-109 (terminals 1,2 and 14) and power 
transistor connector C-120 (terminals 2 and 4).

• Check the AC-ECU signal line for open and short circuit.

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

C-109 (terminals 1 and 2) and power transistor 
connector C-120 (terminals 2 and 4) in good condition?
YES : Go to Step 6.
NO :  Repair the wiring harness. The blower motor should 

operate normally.

STEP 6. Replace the power transistor and check the 
trouble symptom again
Check the trouble symptom again.
Q: Is the check result satisfactory?

YES : The procedure is complete.
NO :  Replace the A/C-ECU.

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-85

INSPECTION PROCEDURE 6: Outside/Inside Air Changeover is not possible.

.

CIRCUIT OPERATION

If the outside/inside air selection damper control 
motor does not operate normally, the outside/inside 
air selection damper control motor system may be 
defective.

.

TROUBLESHOOTING HINTS

• Malfunction of the outside/inside air selection 

damper control motor

• Malfunction of the A/C-ECU

• Damaged harness wires or connectors

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB992006: Extra Fine Probe

•  MB991958: Scan Tool (M.U.T.-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A

AC702640

A/C-ECU

AB

Outside/Inside Air Selection Damper Control Motor Circuit

OUTSIDE/INSIDE AIR 
SELECTION DAMPER
CONTROL MOTOR

AC702208AK

Connectors: C-106, C-108

C-106

C-108 (B)

MANUAL A/C DIAGNOSIS

TSB Revision

HEATER, AIR CONDITIONING AND VENTILATION

55A-86

STEP 1. Using scan tool MB991958, read the diagnostic 
trouble code.

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
Check if an A/C-ECU DTC is set.
(1) Connect scan tool MB991958. Refer to "How to connect the 

Scan Tool (M.U.T.-III) 

P.55A-7

."

(2) Turn the ignition switch to the "ON" position.
(3) Check if the DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?

YES : Go to Step 2.
NO :  Refer to DIAGNOSTIC TROUBLE CODE CHART 

P.55A-11

.

STEP 2. Check outside/inside air selection damper control 
motor connector C-106 and A/C-ECU connector C-108 for 
loose, corroded or damaged terminals, or terminals 
pushed back in the connector.
Q: Are outside/inside air selection damper control motor 

connector C-106 and A/C-ECU connector C-108 in good 
condition?
YES : Go to Step 3.
NO :  Repair or replace the connector. Refer to GROUP 

00E, Harness Connector Inspection 

P.00E-2

. Check 

that the A/C works normally.

STEP 3. Check the wiring harness between A/C-ECU 
connector C-108 (terminals 26, 25, 27, 24 and 29) and 
outside/inside air selection damper control motor 
connector C-106 (terminals 2, 5, 4. 1 and 3).

• Check the AC-ECU signal line for open and short circuit.

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

C-108 (terminals 26, 25, 27, 24 and 29) and 
outside/inside air selection damper control motor 
connector C-106 (terminals 2, 5, 4. 1 and 3) in good 
condition?
YES : Go to Step 4.
NO :  Repair the wiring harness. Check that the A/C works 

normally. 

ZC501967

AC404789

AC701411AB

MB991824

MB991827

MB991910

Data link 
connector