Blower Motor Control

WARNING: This page is about a different car, the 2018 Jaguar XF, 2017 Jaguar XF, and 2016 Jaguar XF. However, it is still accessible from the selected car via links, so may be relevant.

The ATCM monitors a feedback voltage from the blower control module. In response to the feedback voltage, the ATCM provides a drive signal back to the blower control module which is used to regulate the voltage flow across the blower motor and hence regulate blower speed. The blower is provided with a battery voltage feed from the blower relay in the Passenger Junction Box (PJB).

When the blower is in automatic mode, the ATCM determines the blower speed required from comfort algorithms. When the blower is in the manual mode, the ATCM operates the blower at the speed selected on the ICP.

The ATCM also controls blower speed to compensate for the ram effect on intake air produced by forward movement of the vehicle. As vehicle speed, and consequently the ram effect increases, blower speed is reduced.