A/C Control Module Self-Diagnosis

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

Without left/right independent air conditioner

DIAGNOSTIC PROCEDURE CHART

Step	Check	Yes	No
1 SELECT SELF-DIAGNOSIS MODE IN THE CONTROL MODULE. Set the air flow control dial and fan speed control dial to the AUTO position. Start the engine with the A/C switch and the FRESH/RECIRC switch pressed.	Does the self-diagnosis mode operate?	Go to step 2 .	< Ref. to A/C OR SELF-DIAGNOSIS SYSTEMS DO NOT OPERATE , Diagnostics for A/C System Malfunction. >
2 CHECK THE LIGHTING OF THE LED. Make sure that all switch LEDs on the control panel illuminate.	Do all LEDs blink eight times?	Go to step 3 .	Replace the control module.
3 CHECK SENSOR MALFUNCTION. Set the air flow control dial and fan speed control dial to the AUTO position. If the system has trouble for each sensor, the FRESH/RECIRC switch LED blinks or is turned off. If the system has no malfunctions, the FRESH/RECIRC switch LED is illuminated.	Does the FRESH/RECIRC switch LED illuminate?	Go to step 5 .	Go to step 4 .
4 CONFIRM MALFUNCTIONING SENSOR. Set the air flow control dial to AUTO. Turn the fan speed control dial to each mode position, and check each switch LED illumination according to sensor check table. < Ref. to SENSOR CHECK TABLE , OPERATION, Diagnostic Chart for Self-Diagnosis. >	When turning the fan speed control dial to each mode position, does the FRESH/RECIRC switch LED go off?	Go to step 5 .	Repair the defective sensor. < Ref. to DIAGNOSTIC PROCEDURE FOR SENSORS . >
5 CHECK AIR MIX DOOR AND MODE DOOR POSITION OPERATION SIGNALS. Set the air flow control dial to FACE. Turn the fan speed control dial to AUTO. If there is a system malfunction in the air mix door signal or the mode door position signal, the FRESH/RECIRC switch LED goes off or blinks. If the system has no malfunctions, the FRESH/RECIRC switch LED is illuminated.	Does the FRESH/RECIRC switch LED illuminate?	Go to step 8 .	Go to step 6 .
6 CHECK AIR MIX DOOR POSITION DRIVE SIGNALS. Set the air flow control dial to FACE. Place the fan speed control dial in each position and then check each LED illumination conditions. < Ref. to DRIVE SIGNAL CHECK TABLE , OPERATION, Diagnostic Chart for Self-Diagnosis. >	Do the LEDs illuminate in accordance with operation signal table?	Go to step 7 .	Check the air mix door actuator circuit. < Ref. to AIR MIX DOOR ACTUATOR , Diagnostic Procedure for Actuators. >
7 CHECK MODE DOOR POSITION DRIVE SIGNAL. Press the A/C switch. Place the fan speed control dial in each position and then check each LED illumination conditions. < Ref. to DRIVE SIGNAL CHECK TABLE , OPERATION, Diagnostic Chart for Self-Diagnosis. >	Do the LEDs illuminate in accordance with operation signal table?	Go to step 8 .	Check the mode door actuator circuit. < Ref. to MODE DOOR ACTUATOR , Diagnostic Procedure for Actuators. >
8 CHECK OPERATION OF EACH ACTUATOR, BLOWER FAN AND COMPRESSOR CLUTCH. Set the air flow control dial to B/L. Turn the fan speed control dial from AUTO to 7th, and select operating modes. Check the operation of each mode according to operating mode table. < Ref. to OPERATING MODE TABLE , OPERATION, Diagnostic Chart for Self-Diagnosis. > FRESH/RECIRC door Air flow control door Air mix door Blower fan A/C compressor	Does the operation of each mode match to operating mode table?	Turn the fan speed control dial to OFF or the ignition switch to OFF in order to complete self-diagnosis.	Repair the malfunctioning part in accordance with each diagnostic chart.

With left/right independent air conditioner

DIAGNOSTIC PROCEDURE CHART

Step	Check	Yes	No
1 SELECT SELF-DIAGNOSIS MODE IN THE CONTROL MODULE. Start the engine with the A/C switch and the FRESH/RECIRC switch pressed.	Does the self-diagnosis mode operate?	Go to step 2 .	< Ref. to A/C OR SELF-DIAGNOSIS SYSTEMS DO NOT OPERATE , Diagnostics for A/C System Malfunction. >
2 CHECK DISPLAY AND INDICATOR. Check if the screen display and all indicators illuminate.	Do the screen display and all indicators illuminate?	Go to step 3 .	Replace the control module.
3 CHECK SENSOR MALFUNCTION. After illumination of the display and indicator, the Inspection Mode for the sensor is initiated by pressing the fan switch (UP). ("2" illuminates at tenths place of driver's side setting temperature display) When malfunction occurs in each sensor, codes are displayed on the screen. When malfunction does not occur in each sensor, code "20" is displayed on the screen. Identify defective sensors according to the sensor check table. < Ref. to SENSOR CHECK TABLE , OPERATION, Diagnostic Chart for Self-Diagnosis. >	Is "20" displayed on the screen?	Go to step 4 .	Repair the defective sensor. < Ref. to DIAGNOSTIC PROCEDURE FOR SENSORS . >
4 CHECK AIR MIX DOOR AND MODE DOOR POSITION OPERATION SIGNALS. After checking of the sensor, the Inspection Mode for the air mix door and mode door position drive signal is initiated by pressing the fan switch (UP). ("3" flashes at tenths place of driver's side setting temperature display for five seconds) When malfunction occurs in each actuator circuit, codes are displayed on the screen. When malfunction does not occur, code "30" is displayed on the screen. Identify defective actuator circuit according to the drive signal check table. < Ref. to DRIVE SIGNAL CHECK TABLE , OPERATION, Diagnostic Chart for Self-Diagnosis. >	Is "30" displayed on the screen?	Go to step 5 .	Repair the defective actuator circuit. < Ref. to DIAGNOSTIC PROCEDURE FOR ACTUATORS . >
5 CHECK OPERATION OF EACH ACTUATOR, BLOWER FAN AND COMPRESSOR CLUTCH. After checking of the air mix door and mode door position drive signal, the Operation Inspection Mode for the actuator, blower fan and compressor clutch is initiated by pressing the fan switch (UP). ("4" illuminates at tenths place of driver's side setting temperature display) The setting temperature display changes and the operation mode changes each time the mode switch is pressed. Check each operation according to the operating mode table. < Ref. to OPERATING MODE TABLE , OPERATION, Diagnostic Chart for Self-Diagnosis. > FRESH/RECIRC door Air flow control door Air mix door LH Air mix door RH Blower fan A/C compressor	Does each operation match to operating mode table?	System is normal. Turn the ignition switch to OFF to end the self-diagnosis.	Repair the defective part in accordance with each diagnostic chart.