GF91.29-P-0009CAA Electrical Seat Adjustment (ESA)

GF91.29-P-0009CAA Electrical Seat Adjustment (ESA)
- except CODE (275) Memory package (driver seat, steering column, mirrors)
- except CODE (242) Electrically adjustable front passenger seat with memory

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

Function description for electrical seat adjustment (ESA), general
The ESE enables the electrical adjustment of the driver and front passenger seat.
Adjusting possibilities:
- Seat height
- Backrest angle

The electrical seat adjustment (ESE) is described on the driver seat for left-hand drive vehicle as an example, however this also applies for the front passenger seat.

Run-on:
If c. 15R is switched off, the ESE can still be operated for 3 minutes. 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) by 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 transmits the status to the rear SAM control unit with fuse and relay module via the interior CAN. The rear SAM control unit with fuse and relay module then switches on the power supply for the ESE.

Abort conditions
- Overvoltage or undervoltage

The ESE allows the following partial functions:
^ Manual adjustment
^ Anti-lock device
^ Protection function when unlocking seat

Manual adjustment
Actuate and hold down driver seat partially electric seat adjustment switch (S22/1) for seat adjustment:

Then the corresponding seat adjustment motor;
- Driver seat height adjustment seat adjustment motor (M27/2) or
- driver seat backrest inclination seat adjustment motor (M27/5) is actuated.

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

Anti-lock device
Since the ESE 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 respective seat adjustment motor is therefore not switched off until it exceeds a certain temperature threshold.

Protection function when unlocking seat
If the seat is unlocked, the backrest inclination switch contact in the left EASY-ENTRY system limit switch (S159/3) interrupts the electrical line to the driver seat backrest inclination seat adjustment motor so that the backrest cannot be adjusted. During adjustment in the unlocked state, the seat mechanism can be damaged or interrupted. Simultaneously the backrest release switch contact in the left EASY-ENTRY system limit switch transmits a directly read in signal to the rear SAM control unit with fuse and relay module. This transmits signal via the interior CAN (CAN B) to the instrument cluster (A1), which generates a corresponding warning message.

The EASY-ENTRY system limit switch of two contact switches, backrest inclination switch contact switch and backrest release contact switch.