Heat left/right outside mirrors function

D88.79-0003-05

Illustrated on left side of vehicle

M21/6 Driver-side outside mirror

M21/6r1 Mirror heater

M21/7 Passenger-side outside mirror

M21/7r1 Mirror heater

Function requirements:

 Status "Circuit 61 ON" (engine running) present.

 The power windows are not actuated, i.e. the driver-side power window button (S47s1) or passenger-side power window button (S47s2) is not actuated.

 Overvoltage or undervoltage not present.

The mirror heater in the driver-side outside mirror and the mirror heater in the passenger-side outside mirror consist of one heating resistor each, located on a foil on the back of the corresponding mirror lens.The power supply and controlled switch-on and switch-off of the heating resistors is accomplished by the driver door control unit (N69/1). The driver-side and passenger-side outside mirrors can be heated, depending on the outside temperature measured by the outside temperature sensor (B14), with code (J65) Outside temperature indicator.

The SAM control unit (N10) reads the values from the outside air temperature sensor, with code (J65) Outside temperature indicator directly via a discrete line and transmits the temperature value as Controller Area Network (data bus/CAN bus) (CAN) message "T_AUSSEN (outside air temperature)" to the Controller Area bus class B (interior compartment) (CAN-B).

The driver door control unit reads in the message "T_AUSSEN (outside air temperature)" and activates and deactivates the driver-side outside mirror heater as well as the passenger-side outside mirror heater.

The driver-side outside mirror heater and the passenger-side outside mirror heater are activated at an outside temperature of < 15 °C.

The driver-side outside mirror heater and the passenger-side outside mirror heater are deactivated at an outside temperature > 19 °C.

If the temperature received from the outside air temperature sensor, with code (J65) Outside temperature indicator, is implausible, the driver-side outside mirror heater and the passenger-side outside mirror heater are always activated when status "Circuit 61 ON" (engine running) is present.