P0480

DTC P0480: Radiator Cooling Fan Control System Malfunction

Wiring Diagram










DTC Confirmation Procedure

NOTE:

Check to make sure that the following conditions are satisfied when using this DTC confirmation procedure.

- Intake air temp.: -14 °C, 6.8 °F or higher
- Altitude (barometric pressure): 2020 m, 6650 ft or less (540 mmHg, 72 kPa or more).

1) Turn ignition switch turned OFF.
2) Clear DTC with ignition switch ON.
3) Warm up engine until radiator cooling fan starts to operate.
4) Check pending DTC in "ON BOARD TEST" or "PENDING DTC" mode and DTC in "DTC" mode.

DTC Troubleshooting

1.
Was "Engine System Check" performed?
YES
Go to Step 2.
NO
Go to Engine System Check Engine System Check.

2. Check wire circuit.

Disconnect radiator fan control relay No.1 (1) from relay box with ignition switch turned OFF.
Turn ON ignition switch, measure voltage between each engine ground to "BLK/WHT" and "BLU/WHT" wire terminal.





2. Radiator fan relay No. 2

3. Radiator fan relay No. 3

Is voltage 10 - 14 V?
YES
Go to Step 3.
NO
"BLK/WHT" and/or "BLU/WHT" wire open circuit.

3. Check wire circuit.

Connect radiator fan control relay No.1 to relay box with ignition switch turned OFF.
Turn ON ignition switch, measure voltage between vehicle body ground and "C04-3" terminal wire.

Is voltage 10 - 14 V?
YES
Go to Step 7.
NO
Go to Step 4.

4. Check wire circuit.

Disconnect connector from ECM with ignition switch turned OFF.
Disconnect radiator fan control relay No.1 from relay box.
Measure resistance between "G04-3" terminal wire and vehicle ground.

Is resistance infinity?
YES
Go to Step 5.
NO
"BRN" wire shorted to ground circuit.

5. Check wire circuit.

Turn ON ignition switch.
Check voltage between "G04-3" terminal wire and vehicle body ground.

Is voltage 0 V?
YES
Go to Step 6.
NO
"BRN" wire shorted to power supply circuit.

6. Check radiator fan control relay No.1.

Check radiator fan control relay No.1, referring to Radiator Fan Control System Check.

Is result in good condition?
YES
"BRN" wire open circuit.
NO
Replace relay.

7. Check radiator fan control No.1.

Connect connectors to ECM with ignition switch turned OFF.
Run engine at ECT is over 97 °C, 207 °F.
Measure voltage between vehicle body ground and "G04-3" terminal wire.

Is voltage lower 1.5 V?
YES
Go to Step 8.
NO
Faulty ECM.

8. Check radiator fan control.

Disconnect radiator fan control relay No.2 (2), and No.3 (3) from relay box with ignition switch turned OFF.
Run engine at ECT is over 97 °C, 207 °F.
Measure voltage between vehicle body ground and each "BLU/RED" wire terminal.





1. Radiator fan relay No. 1

Is voltage lower 10 - 14 V?
YES
Go to Step 9.
NO
"BLU/RED" wire open circuit.

9. Check wire circuit.

Disconnect connector from ECM with ignition switch turned OFF.
Connect radiator fan control relay No.2 to relay box.
Turn ON ignition switch, measure voltage between vehicle body ground and "G04-34" terminal wire.

Is voltage 10 - 14 V?
YES
Go to Step 10.
NO
Go to Step 11.

10. Disconnect radiator fan control relay No.2 and then connect radiator fan control relay No.3 to relay box.
Turn ON ignition switch, measure voltage between vehicle body ground and "G04-34" terminal wire.

Is voltage 10 - 14 V?
YES
Go to Step 14.
NO
Go to Step 11.

11. Check wire circuit.

Disconnect radiator fan control relay No.2 and No.3 from relay box.
Measure resistance between "G04-34" terminal wire and vehicle body ground.

Is resistance infinity?
YES
Go to Step 12.
NO
"GRN/RED" wire shorted to ground circuit.

12. Check wire circuit.

Turn ON ignition switch.
Check voltage between "G04-34" terminal wire and vehicle body ground.

Is voltage 0 V?
YES
Go to Step 13.
NO
"GRN/RED" wire shorted to power supply circuit.

13. Check radiator fan control relay No.2 and No.3.

Check radiator fan control relay No.2 and No.3, referring to Radiator Fan Control System Check.

Are relays in good condition?
YES
"GRN/RED" wire open circuit.
NO
Replace relay.

14. Check radiator fan control No.2 and No.3.

Connect connectors to ECM with ignition switch turned OFF.
Run engine at ECT is over 102 °C, 216 °F.
Measure voltage between vehicle body ground and "G04-34" terminal wire.

Is voltage lower 1.5 V?
YES
Intermittent trouble.
Check for intermittent refer to Intermittent and Poor Connection Inspection.
If OK, substitute a known-good ECM and recheck.
NO
Faulty ECM.