RS with MTC

Upon ignition on, the A/C-Heater Control Module sends a blower relay on request to the FCM over the PCI Bus. The front blower relay and the rear blower relay, if equipped, are then powered through low side control through FCM pin 30. The relay provides the high side to the blower motor, and the blower speed is governed through low side control in the A/C-Heater Control Module. This circuit is electronically controlled and continuously monitored for malfunctions.