Diagnostic procedure

WARNING: This page is about a different car, the 2005 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

When performing an asterisked (*) troubleshooting inspection, shake the wiring harness and connectors while performing the inspection to discover whether poor contact points are the cause of any intermittent malfunctions. If there is a problem, check to make sure connectors, terminals and wiring harnesses are connected correctly and undamaged.

NO. 8 NO COOL AIR DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	INSPECT AIR BLOW OUT Does air blow out?	Yes	Go to next step.
1	INSPECT AIR BLOW OUT Does air blow out?	No	Go to Step 1 of troubleshooting indexes No. 1 and 2.
2	INSPECT A/C COMPRESSOR OPERATION Start engine. Turn A/C switch and fan switch on. Does A/C compressor operate?	Yes	Go to Step 1 of troubleshooting index No. 7.
2		No	Go to next step.
3	INSPECT FOR PCM DTC Inspect for DTCs related to the PCM onboard diagnostic system. Are any DTCs displayed?	Yes	Go to appropriate inspection procedure.
3		No	Go to next step.
4	INSPECT TO SEE WHETHER MALFUNCTION IS IN CLIMATE CONTROL UNIT OR ELSEWHERE Does cool air blow out when terminal 1P of climate control unit (A/C signal) is grounded?	Yes	Replace climate control unit, then go to Step 17.
4		No	Release short, then go to next step.
5*	INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C SIGNAL CIRCUIT (BETWEEN REFRIGERANT PRESSURE SWITCH AND PCM) OR ELSEWHERE Test voltage at the following terminal of refrigerant pressure switch: Terminal B (A/C signal) Is voltage approximately 12 V?	Yes	Go to Step 7.
5*		No	Go to next step.
6*	INSPECT TO SEE WHETHER MALFUNCTION (LACK OF CONTINUITY) IS IN WIRING HARNESS (BETWEEN REFRIGERANT PRESSURE SWITCH AND PCM) OR PCM Test voltage at PCM A/C signal terminal. Is voltage approximately 12 V?	Yes	Repair wiring harness between PCM and refrigerant pressure switch, then go to Step 17.
6*		No	Inspect PCM, then go to Step 17.
7	INSPECT TO SEE WHETHER MALFUNCTION IS IN REFRIGERANT PRESSURE SWITCH, REFRIGERANT AMOUNT, OR ELSEWHERE Does cool air blow out when terminals A and B of refrigerant pressure switch connector are shorted?	Yes	Go to Step 9.
7		No	Go to next step.
8*	INSPECT TO SEE WHETHER MALFUNCTION IS IN WIRING HARNESS (BETWEEN REFRIGERANT PRESSURE SWITCH AND CLIMATE CONTROL UNIT) OR ELSEWHERE Test voltage at the following terminal of climate control unit. Terminal 1P (A/C signal) Is voltage approximately 12 V?	Yes	Go to Step 10.
8*		No	Repair wiring harness between refrigerant pressure switch and climate control unit, then go to Step 17.
9	INSPECT TO SEE WHETHER MALFUNCTION IS IN REFRIGERANT PRESSURE SWITCH OR REFRIGERANT AMOUNT Inspect refrigerant pressure switch. Is it okay?	Yes	If there is no refrigerant, replace condenser, bleed the refrigerant line for 30 min or more using a vacuum pump, and add refrigerant to specified level, then go to Step 17.
9		No	Replace refrigerant pressure switch, then go to Step 17.
10	INSPECT TO SEE WHETHER MALFUNCTION (LACK OF CONTINUITY) IS IN A/C CONTROL SIGNAL CIRCUIT (BETWEEN A/C RELAY AND PCM) OR ELSEWHERE Does cool air blow out when A/C relay terminal E (A/C control signal) is grounded?	Yes	Release short, then go to next step.
10		No	Go to Step 12.
11*	INSPECT TO SEE WHETHER MALFUNCTION (LACK OF CONTINUITY) IS IN PCM OR WIRING HARNESS (BETWEEN A/C RELAY AND PCM) Test voltage at the PCM A/C relay control signal terminal. Is voltage approximately 12 V?	Yes	Inspect PCM, then go to Step 17.
11*		No	Repair wiring harness between A/C relay and PCM, then go to Step 17.
12*	INSPECT TO SEE WHETHER MALFUNCTION IS IN MAGNETIC CLUTCH OR ELSEWHERE Test voltage at the following terminal of magnetic clutch thermal protector: Terminal A (magnetic clutch operation signal) Is voltage approximately 12 V?	Yes	Inspect magnetic clutch, then go to Step 17.
12*		No	Go to next step.
13	INSPECT FUSE Are A/C relay power supply fuses okay?	Yes	Go to next step.
13	INSPECT FUSE Are A/C relay power supply fuses okay?	No	Replace fuse, then go to Step 17. If fuse burns out immediately, go to next step.
14	INSPECT WIRING HARNESS BETWEEN FUSE BLOCK AND A/C RELAY FOR LACK OF CONTINUITY Test voltages at the following terminals of A/C relay. Terminal A (A/C relay control signal) Terminal C (A/C control signal) Are voltages approximately 12 V?	Yes	Go to next step.
14		No	Repair wiring harness between fuse block and A/C relay, then go to Step 17.
15	INSPECT TO SEE WHETHER MALFUNCTION IS IN A/C RELAY OR WIRING HARNESS (BETWEEN A/C RELAY AND MAGNETIC CLUTCH) AND EVAPORATOR TEMPERATURE SENSOR Test voltage at the following terminal of A/C relay: Terminal D (magnetic clutch operation signal) Is voltage approximately 12 V?	Yes	Inspect wiring harness between A/C relay and magnetic clutch. If above wiring harness is OK, go to next step. If above wiring harness malfunctions, repair wiring harness, then go to Step 17.
15		No	Replace A/C relay, then go to Step 17.
16	INSPECT EVAPORATOR TEMPERATURE SENSOR Inspect evaporator temperature sensor. Is it okay?	Yes	Go to next step.
16		No	Replace evaporator temperature sensor, then go to next step.
17	CONFIRM THAT MALFUNCTION SYMPTOMS DO NOT RECUR AFTER REPAIR Does cool air blow out? (Are the results of refrigerant system performance test okay?)	Yes	Troubleshooting completed. Explain repairs to customer.
17		No	Recheck malfunction symptoms, then repeat from Step 1 if malfunction recurs.