Trailer Recognition Control Unit, Component Description - GF31.19-S-4050TRA
Model 447
With Code E57 (Electrics for trailer socket)
except code XM7 (MOPF II)
Model 447
With Code E58 (Electrics for NAFTA trailer socket)
except code XM7 (MOPF II)
Model 447
With Code Q22 (Trailer coupling, rigid coupling head)
except code XM7 (MOPF II)
Model 447
With Code Q24 (Trailer cross member NAFTA, towing capacity 5000Ibs)
except code XM7 (MOPF II)
Model 447
With Code Q50 (Trailer coupling with removable ball-type head)
except code XM7 (MOPF II)
Location
The trailer recognition control unit (N28/1) is in the sidewall at the rear right.
Task
The trailer recognition control unit (N28/1) has the following tasks:
- Reading in of sensors and signals
- Evaluation of input factors
- Trailer recognition
- Trailer consumer actuation
- Lamp failure indicator
- Emergency light function
- Consumer shutoff
Reading in of sensors and signals
The signals from the trailer recognition control unit (N28/1) are read in via the interior CAN (CAN B). The resultant functions are described in the respective function descriptions.
Evaluation of input factors
The input factors are evaluated by the microprocessor and the corresponding components are actuated.
Trailer recognition
By monitoring the current at the "left turn signal light" and "brake lights" outputs, the trailer recognition control unit (N28/1) detects whether the supply line of the trailer is plugged in or not. When one of the two loads is recognized, the trailer is deemed to be recognized. This status is sent via the interior CAN.
Trailer consumer actuation
The trailer recognition control unit (N28/1) actuates the following trailer components via the 13-pin trailer socket (X58):
- Stop lamp
- Rear fog lamp
- Backup lamp
- Turn signal lamp
- Tail lamp and license plate lamp
Lamp failure indicator
The trailer recognition control unit (N28/1) monitors the function of the bulbs on the trailer. Only faults in the general bulb path are detected. If a failure is detected, a corresponding signal is sent over the interior CAN.
LED version trailer lighting: The minimum current for each lamp path must be 50 mA for reliable lamp failure detection. If this minimum current is undershot, a fault message appears in the multifunction display (A1/1p13) of the instrument cluster (IC) control unit (A1/1) although the trailer lighting is functioning properly.
Emergency light function
If the trailer recognition control unit (N28/1) fails or if there is a corresponding request via the interior CAN, the taillights of the trailer are actuated.
Consumer shutoff
If requested by the signal acquisition and actuation module (SAM) control unit (N10/1), circuit 30g to the 13-pin trailer socket (X58) is switched off. The lighting system of the trailer is not actuated.
| Trailer recognition control unit wiring diagram | Model 447.8 with code E57 (Electrics for trailer socket) except code XM7 (MOPF II) Model 447.8 with code Q50 (Trailer coupling with removable ball-type head) except code XM7 (MOPF II) | PE31.19-S-2101-97VVA | |
| Model 447.6/7 with code E57 (Electrics for trailer socket) except code XM7 (MOPF II) Model 447.6/7 with code E58 (Electrics for NAFTA trailer socket) except code XM7 (MOPF II) Model 447.6/7 with code Q22 (Trailer coupling, rigid coupling head) except code XM7 (MOPF II) Model 447.6/7 with code Q24 (Trailer cross member NAFTA, towing capacity 5000Ibs) except code XM7 (MOPF II) Model 447.6/7 with code Q50 (Trailer coupling with removable ball-type head) except code XM7 (MOPF II) | PE31.19-S-2101-97VVB |