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GF88.79-P-2000LE Heat Left/Right Outside Rearview Mirrors Function



GF88.79-P-2000LE Heat Left/right Outside Rearview Mirrors Function
- as of model year 09


Function requirements, general
^ C. 61 ON (with automatic switch-on)
^ On-board electrical system consumer shutoff not active

Heat left/right outside mirror, general
The outside mirror heater keeps the mirror glasses free of ice and fog.
The outside mirror heater is switched on automatically or manually.

Heat left/right outside mirror, function sequence
The heated outside mirror is automatically switched on and off dependent on the outside temperature and the dew point temperature.
The outside temperature is sensed by the outside temperature indicator temperature sensor (B14) and relayed to the front SAM control unit with fuse and relay module (N10/1) which transmits the signal to the interior CAN.
The dew point temperature is sensed by the KLA multifunction sensor (B31/1) and relayed to the AAC control unit (N22/1), which transmits the signal to the interior CAN.

The left front door control unit (N69/1) (model 221) or left door control unit (N69/1) (model 216) and the right front door control unit (N69/2) (model 221) or right door control unit (N69/2) (model 216) read in the signals and switch the outside mirror heater on or off.

The outside mirror heater is switched on when the vehicle engine is running if
- Outside temperature ≤ Dew point temperature + 2 °C (programmable via STAR DIAGNOSIS)
- outside temperature < 15 °C

The outside mirror heater is switched off when the vehicle engine is running if
- Outside temperature ≥ Dew point temperature + 5 °C (programmable via STAR DIAGNOSIS)
- Outside temperature > 16 °C=

If the dew point temperature value is implausible, the default value is used.

If the outside temperature value received is not plausible, the outside mirror heater is always switched on.

When the rear window heater is switched on and off, the outside mirror heater is also switched on and off.
A signal is transmitted to the rear SAM control unit with fuse and relay module (N10/2) by the upper control panel control unit (N72/1) or AAC control unit and is placed on the interior CAN. The door control units read in the signals and switch the outside mirror heater on and off.

Detailed information is given in the separate function description "Heated rear window (HSS)".