Backup light actuation, function - GF82.10-P-3011CE
MODEL 204.0/2 as of model year 2009/YoM 08
MODEL 204.3
MODEL 204.9
Function requirements, general
- No overvoltage or undervoltage (operating voltage range U ≥ 7 ≤ 17.5 V)
- Circuit 15 ON
The electronic ignition lock control unit (N73) transmits the circuit 15 status to the front SAM control unit with fuse and relay module (N10/1) over the interior CAN (CAN B).
Backup light actuation, general
The backup light actuation enables the traffic lane to the rear of the vehicle to be illuminated when backing up.
Function sequence for backup light actuation
When reverse gear is engaged (transmission 711, 716 (manual transmission)) or gear range "R" (transmission 722 (automatic transmission)) the rear SAM control unit with fuse and relay module (N10/2) activates the backup light actuation.
Vehicles with transmission 711, 716:
Engagement of the reverse gear is defined through the status of the backup lamp switch (S16/2), which is read in directly by the front SAM control unit.
Vehicles with transmission 722.6:
The request to "Engage gear range R" is defined by the corresponding selector lever position.
The electronic selector lever module control unit (N15/5) transmits the selector lever position via drive train CAN (CAN C), CDI control unit (N3/9) (with diesel engine) or ME-SFI [ME] control unit (N3/10) (with gasoline engine) and chassis CAN (CAN E) to the front SAM control unit.
Two microprocessors are installed in the front SAM control unit, one for control of basic functions, e.g. the exterior lights, and the second for control of the central gateway functions. Both processors communicate with each other internally via interior CAN.
The microprocessor for control of the central gateway functions uses the incoming information to generate the "Reverse gear engaged" signal that is independent of the type of transmission and sends this via interior CAN to the rear SAM control unit, and, in vehicles with code (550) Trailer hitch, to the trailer recognition control unit (N28/1).
The rear SAM control unit receives this signal and actuates the left backup lamp (E3e3) and the right backup lamp (E4e3).
The trailer recognition control unit receives this signal and actuates the backup lamp on the trailer via the trailer socket (X58).
To prevent any brief illumination of the backup lamps in vehicles with transmission 722 when changing from gear range "P" to "D" via "R", the request from the front SAM control unit is sent with a delay of t = 500 ms.
| Electrical function schematic for backup light actuation | Model 204.0/2/3 | PE82.10-P-2058-97FAB | |
| Model 204.9 | PE82.10-P-2058-97FAC | ||
| Overview of exterior lights system components | GF82.10-P-9998CE |