PACCAR MX (2004 Emissions) Fault Code: P0528 Fan Speed – Data Valid but Too Low

PACCAR MX (2004 Emissions) Fault Code: P0528 Fan Speed – Data Valid but Too Low

SET CONDITIONS:
The PCI ECU (D420) detects that the fan speed is below 50 rpm.

DIAGNOSTIC CONDITION:
The diagnostic runs when the engine speed is above 1200 rpm.

RESET CONDITION:
This DTC changes to INACTIVE after the diagnosis runs and passes.

POSSIBLE CAUSES:
1. The fan does not rotate freely (for example, fan blade hits the wind tunnel).
2. The sensor or actuator signal wiring is interrupted.
3. The sensor or actuator signal wiring has a short circuit to ground.
4. A malfunction in the power supply of the sensor
5. A malfunction of the electronically controlled fan clutch