Theory Of Operation

The pulse-width modulated (PWM) fan receives a duty cycle signal from the Totally Integrated Power Module (TIPM) on the (K175) Rad Fan High Speed Control circuit. The Low Speed Cooling Fan Relay is not used to control any components and has no external function. The TIPM connects to the Low Speed Cooling Fan Relay through an internal connection and may set a DTC if the Low Speed Cooling Fan Relay is removed or damaged.