Possible causes

– Cooling fan harness and connector
– Faulty cooling fan

When is the code detected?

The P0526 code is detected when the PCM has detected a loss of cooling fan speed signal and the condition is present for at least 11 seconds.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Engine overheating

P0526 GMC Description

The powertrain control module (PCM) uses the cooling fan speed signal in order to determine the actual fan speed in relation to the desired fan speed. The PCM uses the cooling fan speed signal in order to reduce the cooling fan noise and in order to maintain the powertrain cooling requirements. The PCM supplies power and ground to the clutch hall effect sensor of the cooling fan clutch. The hall effect sensor returns a signal pulse through the speed signal circuit in response to the reluctor track, which is located inside the fan clutch. If during operation, the PCM detects a loss of the cooling fan speed signal, DTC P0526 will set.

GMC Technical Service Bulletins for P0526 code