With A/C

Start engine. Turn A/C switch off. If A/C clutch is not engaged, go to next step. If A/C clutch is engaged, go to appropriate A/C SYSTEMS article for diagnosis and repair.

Turn A/C switch and fan switch on. If A/C clutch is engaged, go to next step. If A/C clutch is not engaged, go to appropriate A/C SYSTEMS article for diagnosis and repair.

Turn engine off. Connect scan tool. Turn ignition on. Select PID/DATA MONITOR AND RECORD function. Select A/C SW, A/CP SW and ECT PIDs. Start engine. Monitor all PIDs and cooling fan operation under various conditions. See Fig 1 . Check cooling fan relays. See Fig 2 . For wiring information, see appropriate wiring diagram in WIRING DIAGRAMS article.

Fig 1: Cooling Fan Control Identification

Courtesy of MAZDA MOTORS CORP.

Fig 2: Cooling Fan Relay Check

Courtesy of MAZDA MOTORS CORP.

1. If ECT is less than 212°F (100°C) and A/C switch is off, fans should be off. If fans are on, check the following:
   • Short to ground on Green/Black wire between relay No. 1, relay No. 6 and PCM terminal No. 45.
   • Short to ground on Green wire between relay No. 2, relay No. 5, relay No. 7 and refrigerant pressure switch.
   • Short to ground on Yellow/Red wire between relay No. 2, relay No. 3 and PCM terminal No. 17.
   • Short to ground on Blue/Orange wire between relay No. 4 and PCM terminal No. 12.
   • Fan relay contacts stuck closed.
   • Short to power on Red/Black wire between relay No. 4 and fan motor No. 2.
   • Short to power on Black/Yellow wire between relay No. 1 and fan motor No. 1.
   • Short to power on White/Red wire between relay No. 2 and fan motor No. 1.
2. If fan motor No. 1 does not operate, check the motor.
3. If fan motor No. 1 low speed is okay, but high speed does not operate, check the following:
   • Open power circuit for relay No. 2 or relay No. 3.
   • Fan relay No. 2 or relay No. 3 contacts stuck open.
   • Faulty fan motor No. 1.
   • Open circuit on White/Red wire between relay No. 2 and fan motor No. 1.
   • Open circuit on White/Green wire between fan motor No. 1 and relay No. 3.
   • Open circuit on Black wire between relay No. 3 and ground.
   • Open circuit on Yellow/Red wire between relay No. 2, relay No. 3 and PCM terminal No. 17.
4. If fan motor No. 1 high speed is okay, but low speed does not operate, check the following:
   • Open power circuit for relay No. 4.
   • Fan relay No. 4 contacts stuck open.
   • Open circuit on Blue/Orange wire between relay No. 4 and PCM terminal No. 12.
   • Open circuit on Red/Black wire between relay No. 4 and fan motor No. 2.
   • Faulty fan motor No. 2.
   • Open circuit on Green/Yellow wire between relay No. 1 and fan motor No. 2.
   • Fan relay No. 1 contacts stuck open.
   • Open circuit on Blkack/Yellow wire between relay No. 1 and fan motor No. 1.
   • Faulty fan motor No. 1.
   • Open circuit on Black wire between fan motor No. 1 and ground.
5. If fan motor No. 2 does not operate, check fan motor No. 2.
6. If fan motor No. 2 low speed is okay, but high speed does not operate, check the following:
   • Open power circuit for relay No. 5 or relay No. 7.
   • Fan relay No. 5 or relay No. 6 contacts stuck open.
   • Open circuit on Yellow wire between relay No. 5 and fan motor No. 2.
   • Faulty fan motor No. 2.
   • Open circuit on Green/Yellow wire between fan motor No. 2 and relay No. 7.
   • Open circuit on Black wire between relay No. 7 and ground.
   • Open circuit on Yellow/Red wire between relay No. 2, relay No. 3 and PCM terminal No. 17.
   • Open circuit on Green wire between relay No. 2, relay No. 5, relay No. 7 and refrigerant pressure switch.