What does it mean?
Some vehicles are equipped with a sensor at the end of the cooling fan that detects movement during vehicle operation. The sensor is used to determine if the fan is operating on a vehicle equipped with a fan clutch or to verify that the fan speed commanded by the Powertrain Control Module (PCM) or Engine Control Module (ECM) matches the actual fan speed detected on a vehicle equipped with an electric fan.
The sensor used is a 3-wire Hall effect sensor that uses a 5-volt reference source from the PCM, a ground wire, and a signal wire to the PCM to determine the fan speed. For a P0527 to be triggered, the PCM/ECM has determined that the actual fan speed does not match the desired or commanded speed.
Note: Be careful not to touch an electric fan, as it may turn on even when the vehicle is not running. This code is similar to P0526, P0528, and P0529.
Symptoms
Symptoms of a DTC P0527 may include:
Illumination of the Malfunction Indicator Lamp (also known as the Check Engine Light)
The vehicle may overheat or run hotter than normal
Causes
Potential causes of a P0527 code include:
The fan clutch or electric fan is not operating at the desired or commanded speed
Possible Solutions
Fan Clutch Equipped – Visually check that the fan is spinning while the engine is running. If the fan spins very slowly during a cold start, replace the fan clutch. It may be necessary to use an advanced scan tool to see the actual fan speed versus the desired fan speed.
Electric Fan Equipped – Visually check that the fan turns on and off when the PCM/ECM commands the fan to operate as the engine reaches certain temperatures. The fan may automatically activate when the air conditioning is turned on. Some fans may be activated using an on/off relay or activated by Pulse Width Modulation (PWM) for variable speed fans.
It may be necessary to use an advanced scan tool to see the actual fan speed versus the commanded fan speed. If the fan speed is below specifications, replace the electric fan assembly or the fan motor.