GF46.11-P-0001TA Steering Wheel Heater (LRH), Function

GF46.11-P-0001TA Steering wheel heater (LRH), function
- 211 as of 1.6.04
- with CODE (443) Steering wheel heater


15.03.07 The document has been updated to this date and will no longer be subject to revision.

Component Identification:

General
In order to make hand contact more comfortable and safer at low temperatures, the steering wheel can be heated up via the steering wheel heater (LRH).

Operation takes place via the steering wheel heater switch (S59/1s2), control is taken over by the HS [SIH] and seat ventilation control unit (N25/7).

Function requirements
^ Circuit 15R or circuit 15 ON
^ Interior temperature < 30 degrees C

Switch on steering wheel heater (LRH)
^ Rotate the steering wheel heater switch (S59/1s2) upwards.
^ The signal is read in by the steering column module (N80) and transmitted via the CAN-B (CAN-B) to the HS [SIH] and seat ventilation control unit (N25/7).
^ The heater coil (R22/4r1) is supplied with voltage by the HS [SIH] and seat ventilation control unit (N25/7) via the steering wheel heater electronics (A74).

The temperate of the steering wheel rim is measured by the steering wheel heater electronics via the heater coil temperature sensor (R22/4b1) (A74) and used for the control (target temperature approx. 35 degrees C).

Function indicator
The activated steering wheel heater (LRH) is displayed by the steering wheel heater function indicator (S59/1e1) in the steering wheel heater switch (S59/1s2).

Switching off steering wheel heater (LRH) manually
^ Turn the steering wheel heater switch (S59/1s2) downwards.
^ The signal is read in by the steering column module (N80) and transmitted via the CAN-B (CAN-B) to the HS [SIH] and seat ventilation control unit (N25/7).
^ The HS [SIH] and seat ventilation control unit (N25/7) deactivates the steering wheel heater (LRH).

The steering wheel heater function indicator (S59/1e1) in the steering wheel heater switch (S59/1s2) goes out.

Switching off the steering wheel heater (LRH) automatically
^ Once the maximum heating time has elapsed (continuous heat mode for 15 minutes) the HS [SIH] and seat ventilation control unit (N25/7) is shut off. The steering wheel heater function indicator (S59/1e1) goes out.
^ The HS [SIH] and seat ventilation control unit (N25/7) is shut off at an interior temperature higher than 30 degrees C. The steering wheel heater function indicator (S59/1e1) remains active.

The interior temperature is transmitted by the AAC [KLA] control and operating unit (N22) or by the comfort AAC control and operating unit (N22/7) via the CAN-B (CAN-B).

^ Circuit 15R is switched off.

The timer control continues running for 5 minutes with circuit 15C [] On. If within this period circuit 15R is switched on again, the steering wheel heater (LRH) is also activated again.

Abort conditions
^ During the engine starting process.

The steering wheel heater function indicator (S59/1e1) remains active.

^ In the event of undervoltage or overvoltage.

The steering wheel heater function indicator (S59/1e1) flashes at 1.5 Hz and 50% brightness.

Reading in the steering wheel heater switch (S69/1s2):
The position of the steering wheel heater switch (S59/1s2) is read out by the steering column module (N80) and placed on CAN-B (CAN-B). As long as the steering wheel heater switch (S59/1s2) is operated (turning up or down), the corresponding position is transmitted cyclically. The center position of the steering wheel heater switch (S59/1s2) is not transmitted by the steering column module (N80).