Blower Motor Control

WARNING: This page is about a different car, the 2020 Jaguar XE and 2019 Jaguar XE. However, it is still accessible from the selected car via links, so may be relevant.

The HVAC monitors a feedback voltage from the blower control module. In response to the feedback voltage, the HVAC provides a drive signal back to the blower control module via a LIN bus connection. The blower control module regulates the voltage flow across the blower motor and hence regulate blower speed. The blower control module 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 HVAC determines the blower speed required from comfort algorithms. When the blower is in the manual mode, the HVAC operates the blower at the speed selected on the ICP.

The HVAC 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.