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Switch off seat heater, function - GF91.30-P-2001T

MODEL 211.0/2 with CODE (401) Front deluxe seats, incl. seat heating and seat ventilation with CODE (872) Electrically heated left and right rear seats with CODE (873) Heated left and right front seats 

Switching off manually 

Press the left front HS [SIH] switch (N72/1s10) or the right front HS [SIH] switch (N72/1s11) until the particular LEDs have gone out. On vehicles with code (872) Electrically heated left and right rear seats, press the left rear HS [SIH] switch (S51/3s2) or the right rear HS [SIH] switch (S51/4s2) until the particular LEDs have gone out. The heated seats (HS) can be switched off at any time.

Automatic switch-off via timer control 

The automatic switch-of is controlled by an integrated timer in the

IMPORTANT The operating and function indications of the heated seats (HS) are summarized in the table given below.

Actuation of the HS [SIH] switch (N72/1s10, N72/1s11, S51/3s2 or S51/4s2) Actuated Heating stage Actuated heat output and duration up to the automatic switchover into the next heating stage or until switching off Function indicator in the HS [SIH] switch (N72/1s10, N72/1s11, S51/3s2 or S51/4s2)
press once Heating stage 3 71 to 100 % 5 min 3 red LEDs
press twice Heat stage 2 41 to 70 % 10 minute 2 red LEDs
press three times Heat stage 1 0 to 40 % 20 min 1 red LED
press four times Heated seats (HS) off - None
Press five times Heating stage 3 71 to 100 % 5 min 3 red LEDs

The heated seats (HS) are also shut off under the following criteria: 

When the ignition is switched off, the heated seats (HS) are also switched off. However, the timer control continues to run for a further 5 minutes as long as circuit 15C is on.

If circuit 15R or circuit 15 are switched on again, then the active stage is switched on again according to the timer control.

If the values are dropping below the undervoltage threshold, the heated seats HS [SIH] (loads only) are switched off (timer control continues to run). The heated seats cannot be switched on again until a permissible voltage has been present for longer than 20 seconds.

Undervoltage recognition is indicated by the fact that the particular LEDs are flashing on and off with a frequency of approx. 1.5 Hz and 50 % brightness.

When the overvoltage threshold is exceeded, the heated seats HS [SIH] (loads only) are switched off. The timer control continues to run if the heated seats (HS [SIH]) are switched off due to overvoltage. It is not possible to switch them on again until a permissible voltage is present again.

Additionally, the HS [SIH] and seat ventilation control unit (N25/7) implements the following protective mechanisms: 

If actuation of the heated cushions (R13/1, R13/2 or R13/3 and R13/4) in the driver or front passenger seat and on vehicles with code (872) Electrically heated left and right rear seats of the heated cushions (R13/5, R13/6 and R13/9 or R13/7, R13/8 and R13/10) in the left or right rear seat is recognized without a request being present, the heated seats HS [SIH] are switched off.

If the interior temperature increases to more than 40°C, the heated seats HS [SIH] are switched off.

IMPORTANT If the value for the interior temperature is not available, the value of the outside temperature is used as a backup.

Heated seats/seat ventilation switch location/task On vehicles with code (873) Heated left and right front seats or with code (401) Front deluxe seats, incl. seat heating and seat ventilation GF91.30-P-3004T 
Heated rear seat switch, location/task For vehicles with code (872) Electrically heated left and right rear seats GF91.30-P-3006T 
Upper control panel control unit, location/task/design/function Model 211.0 GF54.21-P-4105T
Model 211.2 GF54.21-P-4105TS
Heated seats/seat ventilation control unit, location/task In vehicles with code (401) Front comfort seats, including seat heater and with code (872) Electrically heated left and right rear seats or in vehicles up to 31.5.05 with code (873) Heated left and right front seats GF91.30-P-3005T 
Front passenger-side SAM control unit with fuse and relay module, location/task/design On vehicles as of 1.6.05 with code (873) Heated left and right front seats and without code (401) Front comfort seats, incl. seat heating and seat ventilation and without code (872) Electrically heated left and right rear seats GF54.21-P-4111T
Electronic ignition switch control unit, location/task   GF80.57-P-4120T
Door control unit rear, location/task/function   GF72.29-P-4117T