GF54.21-P-7010RT | Front SAM control unit, component description | 27.6.06 |
MODEL 251.1 /0 up to Model Year 8
P54.21-2558-06
N10 Front SAM ECU
Location
The front SAM control unit is located in the right underfloor assembly below the front seat.
General
For data exchange purposes the front SAM control unit is connected to the Controller Area Network bus class B (interior) (CAN-B).
Task
The front SAM control unit reads in the following signals, sensors and switches, actuates the function and switch and controls illumination and then actuates the following relay and consumers by way of semiconductor switches.
Control
Front exterior lights
Footwell lamps
Washer nozzle heater
Front wiper park position heater
Front wiper system
Windshield washer fluid pump
Headlamp cleaning system
(for headlamp cleaning system, code 600)
Heated windshield washer system
(for heated windshield washer system, code 875)
Heated front seats via a timer control
Power windows for rear side windows
Left rear door central locking system
Additional battery charging process (G1/7)
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Reading in and outputting the following signals:
Circuit 31b
Circuit 61 (engine 113 only)
Circuit 58d
Air suspension wake-up signal
Reading in following switches, pickups and sensors:
Left rear power window switch (S21/3)
Right rear power window switch (S21/4)
Brake fluid indicator switch (S11)
Parking brake switch (S12)
Coolant level indicator switch (S41)
Windshield washer system fluid level indicator switch (S42)
Left front brake pad contact sensor (S10/1)
Right front brake pad contact sensor (S10/2)
Left rear brake pad contact sensor (S10/3)
Right rear brake pad contact sensor (S10/4)
The front SAM control unit reads in the parking brake indicator switch and transmits the signal to the CAN-B.
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When the parking brake is tightened and the wheel pulse counter Delta does not change for a set time (t = 2s), the driver-side instrument panel PTS warning indicator (A44/1) and rear dome lamp PTS warning indicator (A44/3) are deactivated.
Switching internal relay
Safety relay for switching off heated seats, if an implausible signal is recognized.
Switching consumers via semiconductor switches
Left high beam (E1e1)
Left low beam (E1e2)
Left standing and parking lamp (E6/13)
Left turn signal lamp (E1e5)
Right high beam (E2e1)
Right low beam (E2e2)
Right standing and parking lamp (E6/14)
Right turn signal lamp (E2e5)
Left front fog lamp (E5/1)
Right fog lamp (E5/2)
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Right front footwell lamp (E17/15)
left front footwell lamp (E17/16)
Right rear footwell lamp (E17/17) (SA)
Left rear footwell lamp (E17/18) (SA)
Additional battery
Windshield washer fluid pump (M5/1)
SRA pump (M5/2)
Left rear power window motor (M10/5)
Right rear power window motor (M10/6)
Left rear door CL [ZV] motor (M14/8)
Center washer nozzle heater (R2/1)
Left heated windshield washer nozzle (R2/2)
Right washer nozzle heater (R2/3)
Left front seat heated cushion (R13/1)
Left front backrest heated cushion (R13/2)
Right front seat cushion heater element (R13/3)
Right front backrest seat cushion heater element (R13/4)
Air spring wake-up signal
Left front side-marker lamp (E6/1)
(with code 494 USA version)
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Right front side-marker lamp (E6/2)
(with code 494 USA version)
Left center air outlet illumination (E10/1)
Left air outlet illumination (E10/2)
Right air outlet illumination (E10/3)
Right center air outlet illumination (E10/4)
Switching of following relay:
Fanfare horn relay (F58kF)
Wiper level relay 1/2 (F58kA)
Wiper ON/OFF relay (F58kB)
Circuit 15 relay (F58kH)
Heated seats actuation
The heating resistors of the seats for driver and front passenger are actuated by the front SAM control unit in accordance with the following tables:
Operation of heated seat switch with function indicator
Heating stage | Heater capacity | Duty cycle (on) | Function indicator |
1 | Low | 0 - 40 % | 1 LED |
2 | middle | 41 - 70 % | 2 LEDs |
3 | high | 71 - 100 % | 3 LEDs |
Switch actuation | Actuation | Function indicator |
None | Heating OFF | No LED switched on |
Once | Heating stage 3 on | 3 LEDs |
2 times | Heating stage 2 on | 2 LEDs |
3 times | Heating stage 1 on | 1 LED |
4 times | Heating OFF | No LED switched on |
5 times | Heating stage 3 on | 3 LEDs |