INSPECTION PROCEDURE 1: When The A/C Is Operation, Temperature Inside The Passenger Compartment Does Not Decrease (Cool Air Is Not Emitted): Diagnosis

WARNING: This page is about a different car, the 2012 Mitsubishi Lancer. However, it is still accessible from the selected car via links, so may be relevant.

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 connecting 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) ."
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 DTC set?
  1. YES: Refer to DIAGNOSTIC TROUBLE CODE CHART .
  2. NO: Go to Step 2.
    
    Fig 1: Connecting Scan Tool To Data Link Connector
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
STEP 2. Check that the blower motor operation when the blower knob is moved to the "Maximum air volume" position.
1. Turn the ignition switch to the "ON" position.
2. Turn the blower knob to the "Maximum air volume" position
  Q: Does the blower motor operate when the blower knob is moved to the "Maximum air volume" position?
  1. YES: Go to Step 3.
  2. NO: Refer to INSPECTION PROCEDURE 4 "BLOWER FAN AND MOTOR DO NOT TURN" .
STEP 3. Check the rear window defogger and outside/inside air selection damper control motor operation.
1. Turn the ignition switch to the "ON" position.
2. Check the engine running.
3. Check the operations of rear window defogger and outside/inside air selection damper control motor.
  Q: Do the rear window defogger and outside/inside air selection damper control motor work normally?
  1. YES: Refer to INSPECTION PROCEDURE 3 "THE A/C COMPRESSOR DOES NOT WORK" .
  2. NO: Refer to INSPECTION PROCEDURE 2, "MALFUNCTION OF THE A/C-ECU POWER SUPPLY SYSTEM" .