Left front seat control unit, component description - GF91.29-P-5230SX

MODEL 221.0/1, 216.3 up to Model Year 08 

Location 

The left front seat control unit is located on the seat cushion frame of the driver seat (1).

Tasks 

The left front seat control unit has the following tasks:

• Actuation of the seat adjustment
• Actuation of seat belt comfort fit feature
• Control of lumbar support adjustment (without code (409) Left/right front multicontour seats and without code (432) Left and right dynamic multicontour seat)
• Control of heated seats HS [SIH] (on model 221 with code (873) Right and left front seat heaters or code (401) Front comfort seats, incl. seat heating and seat ventilation and on model 216)
• Control of seat ventilation (with code (401) Front comfort seats, incl. seat heating and seat ventilation)
• Control of memory function (on model 221 with code (275) Memory package (driver seat, steering column, mirrors) and on model 216)
• Control of easy entry/exit feature (on model 221 with code (275) Memory package (driver seat, steering column, mirrors) and on model 216)
• Actuation of footwell illumination in rear (on model 221)

Discrete outputs 

Voltage supply for the following components:

• Left rear footwell lamp (E17/18) (on model 221)
• Left front seat fore/aft adjustment motor (M27/1)
• Left front head restraint motor (M27/4)
• Left front backrest angle adjustment motor (M27/5)
• Left front seat cushion fore/aft motor (M27/8)
• Left front seat cushion inclination motor (M27/9)
• Left front seat height adjustment motor (M27/10)
• Left front seat belt comfort solenoid (K18/4)
• Left front seat belt lock relay (K18/2) (on model 216)
• Left front seat heated cushion (R13/1) (on model 221 with code (873) Right and left front seat heaters or code (401) Front comfort seats, incl. seat heating and seat ventilation and on model 216)
• Left front backrest heated cushion (R13/2) (on model 221 with code (873) Right and left front seat heaters or code (401) Front comfort seats, incl. seat heating and seat ventilation and on model 216)
• Left front seat cushion ventilation motor group (M18/9) (with code (401) Front comfort seats, incl. seat heating and seat ventilation)
• Left front seat backrest ventilation motor group (M18/10) (with code (401) Front comfort seats, incl. seat heating and seat ventilation)

Discrete inputs 

• Circuit 30
• Circuit 31
• Hall sensors of the motors (M27/1, M27/4, M27/5, M27/8, M27/9 and M27/10)
• Driver lumbar support regulator control unit (N32/23) (without code (409) Left/right front multicontour seats and without code (432) Left and right dynamic multicontour seat)
• Vehicle-sensitive seatbelt lock sensor (A60) (on model 216)
• Left front seat backrest angle microswitch (S91/1) (on model 216)

The left front seat control unit serves as a contact point for:

• Left front seat ventilation blower regulator (N29/5) (with code (401) Front comfort seats, incl. seat heating and seat ventilation)
• Driver lumbar support regulator control unit (N32/23) (without code (409) Left/right front multicontour seats and without code (432) Left and right dynamic multicontour seat)
• Left front multicontour backrest control unit (N32/15) (with code (432) Left and right dynamic multicontour seat)

CAN signals 

The left front seat control unit is an interior CAN participant.