DTC P0481 [LF]: Notes

DTC P0481 (LF) DETECTION CONDITION AND POSSIBLE CAUSE

DTC P0481	Cooling fan relay No. 2 control circuit malfunction
DETECTION CONDITION	The PCM monitors the cooling fan relay No. 2 control signal voltage and current. If the following conditions are met, the PCM determines that there is the cooling fan relay No. 2 control circuit problem. The PCM turns the cooling fan relay No. 2 off, but the voltage of the cooling fan relay No. 2 control signal remains low. The PCM turns the cooling fan relay No. 2 on, but the current of the cooling fan relay No. 2 control signal remains high. Diagnostic support note This is a continuous monitor (other). The MIL does not illuminate. FREEZE FRAME DATA (Mode 2/Mode 12) is available. The DTC is stored in the PCM memory.
POSSIBLE CAUSE	Open circuit or short to ground in cooling fan relay No. 2 power supply circuit Short to ground in wiring harness between battery positive terminal and cooling fan relay No. 2 terminal E Cooling fan relay No. 2 power supply circuits related fuse malfunction Open circuit in wiring harness between battery positive terminal and cooling fan relay No. 2 terminal E Cooling fan relay No. 2 malfunction Short to ground in wiring harness between cooling fan relay No. 2 terminal A and PCM terminal 1N PCM connector or terminals malfunction Short to power supply in wiring harness between cooling fan relay No. 2 terminal A and PCM terminal 1N Open circuit in wiring harness between cooling fan relay No. 2 terminal A and PCM terminal 1N PCM malfunction
Courtesy of MAZDA MOTORS CORP.

DTC P0481

Cooling fan relay No. 2 control circuit malfunction

DETECTION CONDITION

The PCM monitors the cooling fan relay No. 2 control signal voltage and current. If the following conditions are met, the PCM determines that there is the cooling fan relay No. 2 control circuit problem.
- The PCM turns the cooling fan relay No. 2 off, but the voltage of the cooling fan relay No. 2 control signal remains low.
- The PCM turns the cooling fan relay No. 2 on, but the current of the cooling fan relay No. 2 control signal remains high.

Diagnostic support note

This is a continuous monitor (other).
The MIL does not illuminate.
FREEZE FRAME DATA (Mode 2/Mode 12) is available.
The DTC is stored in the PCM memory.

POSSIBLE CAUSE

Open circuit or short to ground in cooling fan relay No. 2 power supply circuit
- Short to ground in wiring harness between battery positive terminal and cooling fan relay No. 2 terminal E
- Cooling fan relay No. 2 power supply circuits related fuse malfunction
- Open circuit in wiring harness between battery positive terminal and cooling fan relay No. 2 terminal E
Cooling fan relay No. 2 malfunction
Short to ground in wiring harness between cooling fan relay No. 2 terminal A and PCM terminal 1N
PCM connector or terminals malfunction
Short to power supply in wiring harness between cooling fan relay No. 2 terminal A and PCM terminal 1N
Open circuit in wiring harness between cooling fan relay No. 2 terminal A and PCM terminal 1N
PCM malfunction

Courtesy of MAZDA MOTORS CORP.