GF91.29-P-0004CW Electric Seat Adjustment (ESA) Function

GF91.29-P-0004CW Electric Seat Adjustment (ESA) Function
- except CODE (275) Memory package (driver seat, steering column, mirrors)
- up to Model Year 8

General
The electric seat adjustment (ESA [ESV]) allows the driver and front passenger seat to be adjusted.

Adjusting possibilities:
^ Seat height
^ Backrest angle
^ Longitudinal seat position (only (United States Of America) and (Canada))
^ Seat inclination (only (United States Of America) and (Canada))

Function requirements
^ Electric seat adjustment (ESA [ESV]) operational
^ Circuit 15R ON or
^ Run-on active

Run-on:
If circuit 15R has been switched off, then the ESA can still be operated

for t = 3 min. If a circuit status change or a door status change occurs within the run-on time, the run-on function starts again. The circuit status is received by the rear SAM control unit with fuse and relay module (N10/2) from the electronic ignition lock control unit (N73) via the interior CAN.

The door status is detected by the left front door lock (A85) and the right front door lock (A85/1). The respective door lock is read in by the left front door control unit (N69/1) or the right front door control unit (N69/2), which transmits the status to the rear SAM control unit via the interior CAN.

The ESA provides the following subfunctions:
^ Manual seat adjustment
^ Anti-lock device

Manual seat adjustment

Function sequence
For seat adjustment the relevant switch must be operated and held in place.
^ Without (United States Of America) and (Canada):
- Driver seat partially electric seat adjustment switch (S22/1)
- Front passenger seat partially electric seat adjustment switch (S23/1)

^ With (United States Of America) and (Canada):
- Left front seat adjustment switch group (S22)
- Right front seat adjustment switch group (S23)

The relevant seat adjustment motor is then actuated:

Driver seat
^ Driver seat height adjustment motor (M27/2)
^ Driver seat backrest inclination adjustment motor (M27/5)

Also with (United States Of America) and (Canada):
^ Driver seat fore/aft adjustment motor (M27/1)
^ Driver seat inclination adjustment motor (M27/3)

Passenger seat
^ Front passenger seat height adjustment motor (M28/2)
^ Front passenger seat backrest inclination adjustment motor (M28/5)

Also with (United States Of America) and (Canada):
^ Front passenger seat fore/aft adjustment motor (M28/1)
^ Front passenger seat inclination adjustment motor (M28/3)

The seat adjustment motor power supply is directly provided by the rear SAM control unit via the relevant seat adjustment switch.

The function is aborted in the event of overvoltage or undervoltage.

Anti-lock device
Since the ESA does not have any sensors or its own control unit, anti-locking protection is provided by a thermal release in the seat adjustment motors. This causes the seat adjustment motor to shut off after a certain temperature threshold is exceeded if it becomes blocked.