Possible Causes
Faulty Starter/Generator Control Module Cooling Fan Relay
Starter/Generator Control Module Cooling Fan Relay harness is open or shorted
Starter/Generator Control Module Cooling Fan Relay circuit poor electrical connection
الأسباب المحتملة
Possible Symptoms
Engine Light ON (or Service Engine Soon Warning Light)
الأعراض المحتملة
Description
The Starter/Generator Control Module (SGCM) controls the coolant fan operation by applying voltage to the coolant fan relay control circuit with an internal solid state device called a driver. When the SGCM is commanding the relay ON, the voltage of the control circuit should be low, near 0 volts. When the SGCM is commanding the relay OFF, the voltage potential of the control circuit should be high, near 12 volts.
The SGCM monitors the relay control circuits for the following conditions:
– Short to ground
– Short to voltage
An open circuit
If the SGCM detects an improper voltage level on the coolant fan relay control circuit, then DTC P1AC1 or P1AC2 will set and the driver will be disabled.