GF91.29-P-0009FLA Electrical Seat Adjustment (ESA), Function

GF91.29-P-0009FLA Electrical Seat Adjustment (ESA), Function
- except CODE (275) Electrically adjustable front seats with memory package

Function requirements, general
^ Circuit 15R ON or
^ Run-on active

Function description for electrical seat adjustment (ESE), general
The electrical seat adjustment is described as an example on the driver seat for left-hand drive vehicles; this applies analogously for the passenger seat.

The electric seat adjustment allows the electrical adjustment of the driver and front passenger seat.

Adjusting possibilities:
- Seat height
- Backrest angle
- Seat inclination

Delayed-off running
The lumbar support adjustment can still be adjusted for t = 180 s after c. 15 R has been switched off. If a change in the circuit status or in the door status occurs during the run-on time, the run-on function begins anew.

The rear SAM control unit with fuse and relay module (N10/2) receives the circuit status via the interior CAN (CAN B) from the electronic ignition lock control unit (N73).

The door status is sensed by the left front door lock (A85) and right front door lock (A85/1). The corresponding door lock is read in by the left front door control unit (N69/1) or right front door control unit (N69/2), which is transmitted to the rear SAM control unit with fuse and relay module via the interior CAN.

Abort conditions
- Overvoltage or undervoltage

The electric seat adjustment enables the following subfunctions:
^ Manual seat adjustment
^ Anti-lock device

Manual seat adjustment
Hold down and actuate corresponding switch for seat adjustment:
- Driver seat electrical seat adjustment switch (S22/1)

Then the corresponding seat adjustment motor is actuated:
- Driver seat height adjustment motor (M27/2)
- Driver seat inclination adjustment motor (M27/3)
- Driver seat backrest inclination adjustment motor (M27/5)

The power for the seat adjustment motors is supplied by the rear SAM control unit with fuse and relay module directly via the electrical seat adjustment switch.

Anti-lock device
Since the electrical seat adjustment does not have a sensor system or its own control unit, the antilock device is actuated by means of a thermal fuse in the seat adjustment motors. In the event of blocking, the seat adjustment motor is thus only switched off if it exceeds a certain temperature threshold.