Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Blower Fan






Blower fan

Blower fan




The blower fan is brushless, of the permanent magnet type. It supplies airflow through the vehicle, and must be running for the climate control to connect.
The blower fan is controlled via a PWM signal from the Central electronic module (CEM). The Climate control module (CCM) controls the speed of the blower fan with a request to the Central electronic module (CEM) via the CAN network.
The blower fan can be diagnosed via the Central electronic module (CEM), among others, via a PWM control signal that it sends back to the Central electronic module (CEM).