Mazda Mazda6 Workshop Manual Supplement page 382

Cooling Fan No.1/Cooling Fan No.2 Control System Inspection
Cooling fan No.1/cooling fan No.2 system operation
Engine condition
ECT below 100°C
{212°F}
ECT above 100°C
{212°F} (until below
97°C {207°F})
ECT above 108°C
{228°F} (until below
105°C {230°F})
A/C and fan switches
are on.
ECT sensor
malfunction
Cooling fan relay No.2
1. Connect the WDS or equivalent to DLC-2.
2. Verify that ECT PID is below main fan operating temperature.
3. Verify that A/C switch and fan switch are off.
4. Turn the engine switch to ON.
5. Verify that the cooling fan No.2 is not operating.
• If the cooling fan No.2 is operating:
(1) Select FAN PID.
(2) Send OFF and verify the cooling fan No.2 is off.
• If the cooling fan No.2 is on, inspect the following.
— Cooling fan relay No.2 stuck in closed position
— Short to GND circuit between cooling fan relay No.2 and PCM terminal 76
— Short to power in circuit at cooling fan relay No.2
— DTC for ECT sensor (P0117, P0118)
• If the cooling fan relay No.2 is off, inspect the following.
— Short to GND circuit between refrigerant pressure switch and PCM terminal 84
— DTC for ECT sensor (P0117, P0118)
6. Start the engine.
7. Verify that the cooling fan No.2 is operating when engine is hot.
• If the cooling fan No.2 does not operate, perform the following.
1. Connect WDS or equivalent to the DLC-2.
2. Select FAN PID.
3. Operate cooling fan No.2 by sending ON command.
4. Inspect if the operation sound is heard from the cooling fan relay No.2.
• If the operation sound is heard, inspect the wiring harness, connectors and cooling fan motor No.2.
• If the operation sound is not heard, inspect cooling fan relay No.2 and open circuit wiring harness
and connectors.
8. Turn the A/C switch and fan switch on.
9. Verify that cooling fan No.2 is operating.
• If fan does not operate, inspect A/C system.
Cooling fan relay No.1
1. Verify that A/C switch and fan switch are off.
2. Start the engine and let it idle.
3. Verify that the cooling fan No.1 is not operating.
• If cooling fan No.1 is operating, inspect for the following.
— Cooling fan relay No.1 is stuck in closed position.
— Short to power in circuit between cooling fan relay No.1 and cooling fan No.1
— Short to GND in circuit between refrigerant pressure switch and PCM terminal 84
— Short to GND circuit between cooling fan relay No.1 and PCM terminal 102
4. Turn the A/C switch and fan switch on.
5. Verify that the cooling fan No.1 is operating and operation sound of A/C compressor magnetic clutch is heard.
F2–230
TROUBLESHOOTING
Cooling fan Cooling fan
relay No.2 relay No.1
OFF OFF
ON OFF
ON ON
ON ON
ON ON