Lumbar adjustment function - GF91.29-P-0008FQ
MODEL 218 with CODE 275 (Electrically adjustable front seats memory package) without CODE 409 (Left/right front multicontour seat) without CODE 432 (Active multicontour seat)
Function requirements, general
- Circuit 15R ON or run-on active
- No overvoltage or undervoltage
Run-on:
If circuit 15R is switched off, the lumbar support can still be set for t = 180 s. If, during the run-on time, the circuits status or the door status is changed, the run-on time starts again.
The electronic ignition lock control unit sends the status of circuit 15 via the interior CAN to the rear SAM control unit.
The door status is recorded by the front door rotary tumbler switches.
Each front door control unit directly reads in the status of the corresponding front door rotary tumbler switch and sends it to the rear SAM control unit via interior CAN.
The power supply of the respective lumbar support adjustment control unit is provided by the driver seat control unit or the front passenger seat control unit. The rear SAM control unit switches the power supply for the driver seat control unit or the front passenger seat control unit depending on the door status, the circuit status and the run-on time.
Lumbar support adjustment, general
In order to provide optimum support for the vertebral column, the backrests on the driver and front passenger seats contain a lumbar support unit.
The lumbar support unit consists of the following components:
- two air cushions
- Lumbar support pneumatic pump
- Lumbar support adjustment control unit
Function sequence for lumbar support adjustment
The adjustment of the lumbar support is performed via the lumbar support adjustment switch. Pressing of the lumbar support adjustment switch is read in directly by the lumbar support adjustment control unit. The lumbar support adjustment control unit controls the corresponding inflation or deflation of the air cushions via integrated valves.
The lumbar support pneumatic pump is directly actuated by the lumbar support adjustment control unit for the compressed air supply. In the respective lumbar support adjustment control unit, pressure sensors are integrated that record the pressure values in the air cushions. The respective lumbar support adjustment control unit transmits these directly to the driver seat control unit or the front passenger seat control unit.
The memory function can be used to store the current setting for the lumbar support, together with other settings, and retrieved when required. Detailed information about this can be found in the function description "Electrical seat adjustment (ESA), function".
| Electrical function schematic, lumbar support adjustment | PE91.29-P-2055-97XAA | ||
| Overview of system components, electric seats | GF91.29-P-9992FQ |