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Switch on seat heater, function - GF91.30-P-2000T

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 

Function requirements: 

Function of heated driver or front passenger seats 

Each operation of the left front HS [SIH] switch (N72/1s10) or the right front HS [SIH] switch (N72/1s11) is read in by the upper control panel control unit (N72/1). The upper control panel control unit (N72/1) transmits the enable command via the Controller Area Network Bus class B (interior) (CAN-B) for activating the integrated heated cushions (R13/1, R13/2 and R13/3, R13/4) to the

The feedback of the switched-on heating stage is transmitted via the integrated LEDs in the left front HS [SIH] switch (N72/1s10) or in the right front HS [SIH] switch (N72/1s11).

Switching on the heated driver or front passenger seats as a function of the interior temperature 

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

Function of the left rear seat heater (with code (872) Electrically heated left and right rear seats) 

Pressing the left rear HS [SIH] switch (S51/3s2) is read in by the left rear door control unit (N69/3) via the switching bus, which forwards the switch-on command to the HS [SIH] and seat ventilation control unit (N25/7) via CAN-B depending upon the number of operations.

The HS [SIH] and seat ventilation control unit (N25/7) actuates the integrated heated cushions (R13/5, R13/6, and R13/9).

The feedback of the switched-on heating stage is transmitted via the integrated LEDs in the left rear HS [SIH] switch (S51/3s2).

Function of the right rear seat heater (with code (872) Electrically heated left and right rear seats) 

Pressing the right rear HS [SIH] switch (S51/4s2) is read in by the right rear door control unit (N69/4) via the switching bus, which forwards the switch-on command to the HS [SIH] and seat ventilation control unit (N25/7) via CAN-B depending upon the number of operations.

The HS [SIH] and seat ventilation control unit (N25/7) actuates the integrated heated cushions (R13/7, R13/8, and R13/10).

The feedback of the switched-on heating stage is transmitted via the integrated LEDs in the right rear HS [SIH] switch (S51/4s2).

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 Function indicator in the HS [SIH] switch (N72/1s10, N72/1s11, S51/3s2 or S51/4s2)
press once Heating stage 3 71 to 100 % 3 red LEDs
press twice Heat stage 2 41 to 70 % 2 red LEDs
press three times Heat stage 1 0 to 40 % 1 red LED
press four times Heated seats (HS) off - None
Press five times Heating stage 3 71 to 100 % 3 red LEDs
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