DTC P0480: Cooling Fan Relay Control Circuit: Description

PCM controls cooling fan motor by controlling cooling fan relay. Cooling fan motor runs whenever ECT is greater than 222°F (105.5°C), A/C relay is commanded on or low/high fault exists in ECT sensor circuit. PCM controls cooling fan relay by controlling an internal drive that pulls relay coil circuit to ground. Relay coil circuit is monitored for low and high voltage faults. DTC sets when cooling fan relay is being commanded off and feedback voltage at PCM is low.