Volvo All Engines (2010 Emissions) Fault Code: SPN 4813 FMI 4 PID: PSID 72 Engine Oil Thermostat Bypass Valve Opening

Electronic Viscous Fan: The Electronic Fan Drive contains a solenoid that controls the flow of fluid between reservoirs in the fan drive housing and cover. The Engine Control Module (ECM) provides a (PWM) Pulse Width Modulation signal to the solenoid and controls solenoid operation to optimize fan speed, based on coolant temperature, intake air temperature and A/C load.

Conditions for diagnostic trouble code (DTC):
1) The voltage at pin A14.EA:26 is below normal value

Observable symptoms
1) The fan will rotate at full speed at low engine speed
2) At high engine speeds, the fan will either be disengaged or run at low fan speed

Wiring harness
1) Connector
2) Solenoid valve, engine fan