The ambient air temperature sensor is connected via a cable to the GEM. It measures the outside air temperature to an accuracy of around +-0.5 C.
The GEM broadcasts the ambient air temperature on the medium speed CAN bus, where it can be evaluated by various systems.
Brake fluid level
The brake fluid level switch is connected via a cable to the GEM.
The GEM transmits a message on the medium speed CAN bus. The instrument cluster then transfers this message to the high speed CAN bus where it is made available for various other functions.
Automatic headlamps
Refer to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).
Combined rain sensor/light sensor
Refer to: Exterior Lighting (417-01 Exterior Lighting, Description and Operation).
Windshield wash/wipe system
Refer to: Wipers and Washers (501-16 Wipers and Washers, Description and Operation).
Anti-theft
Refer to: Anti-Theft - Active (419-01 Anti-Theft - Active, Description and Operation).
Electric booster Heater
Refer to: Auxiliary Climate Control (412-02 Auxiliary Climate Control, Description and Operation).
Climate control
Refer to: Climate Control (412-01 Climate Control, Description and Operation).