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Trailer Recognition Control Unit, Component Description - GF31.19-S-4050A

Model 447 

With Code E57 (Electrics for trailer socket) 

With Code Q22 (Trailer coupling, rigid coupling head) 

With Code Q50 (Trailer coupling with removable ball-type head) 

With Code XM7 (MOPF II) 

Fig 1: Trailer Recognition Control Unit Components Location - Model 447 With Code E57, Q22, Q50, XM7
G16501059Courtesy of MERCEDES-BENZ USA

Trailer recognition (AAG) control unit, shown on Model 447.8 

IMPORTANT The numbers on the pins indicate the pin numbering of the slots.

IMPORTANT The numbers on the pins indicate the pin numbering of the slots.

Trailer recognition (AAG) control unit, shown on Model 447.8 

G16501060Courtesy of MERCEDES-BENZ USA

Overview 

This document contains information on:

General information 

The trailer recognition (AAG) control unit (N28/1) is installed in the vehicle at the right rear near the D-pillar under the side trim.

Function 

The trailer recognition (AAG) control unit (N28/1) is used to monitor and control functions related to the trailer and the trailer coupling.

The following input parameters and initial parameters are read in or output over direct lines by the trailer recognition control unit (N28/1):

Input parameters over a direct line Initial parameters over a direct line
Terminal 15 -
Terminal 30 -
Terminal 31 -
Terminal 54 -
Left and right turn signal indicators -
Left and right tail lights -
Rear fog lamp -
Reversing light -
Input parameters and initial parameters over the vehicle interior CAN (CANB) Additional information
Battery module 48 V battery (A66) With code M56 (48V technology)
Signal acquisition and actuation module (SAM) control unit (N10/1) -
Anti-theft alarm system (ATA) control unit (N26/6) With code FY1 (Anti-Theft Protection Package)
Parameterizable special module (PSM) control unit (N26/16) With code ED5 (Parameterizable special module)
With code JO3 (OLU Connect Unit)
With code ZK0 (EASY UP pop-up roof, electric)
With code ZK0 (Electrohydraulic pop-up roof)
With code ZK7 (MARCO POLO equipment line)
Driver's seat adjustment control unit with memory (N32/5) With code SF1 (Electrically adjustable driver's seat)
Front passenger seat adjustment control unit with memory (N32/6) With code SF2 (Electrically adjustable front passenger seat)
1st rear seat row seat heating/ventilation control unit, left (N32/12) With code H05 (Rear seat climate control, 1st seat row)
With code U90 (Left, 1st seat row luxury seat)
1st rear seat row seat heating/ventilation control unit, right (N32/13) With code H05 (Rear seat climate control, 1st seat row)
With code U91 (1st seat row luxury seat, right)
2nd rear seat row seat heating/ventilation control unit, left (N32/14) With code H07 (Rear seat climate control, 2nd seat row)
With code U96 (Luxury seat, 2nd seat row, left)
2nd rear seat row seat heating/ventilation control unit, right (N32/15) With code H07 (Rear seat climate control, 2nd seat row)
With code U97 (Luxury seat, 2nd seat row, right)
Left front door control unit (N69/3) -
Right front door control unit (N69/4) -
Left sliding door control unit (E-LSTL) (N69/7) With code (T56) Electrical operation for left sliding door
Right sliding door control unit (E-LSTR) (N69/9) With code T55 (Electrical operation for right sliding door)
Overhead control panel control unit (OCP) (N70) With code D34 (Panoramic sliding sunroof)
With code LC4 (Comfort overhead control panel)
With code FY1 (Anti-Theft Protection Package)
Electronic ignition lock (EZS) control unit (N73/8) -
Panoramic sliding sunroof (PSD) control unit (N98) With code D34 (Panoramic sliding sunroof)
Ambient lighting control unit (N162/1) Model 447.8
With code LE3 (Ambient lighting with 64 colors in cockpit and rear passenger compartment),
With code LE4 (Ambient lighting with 64 colors in cockpit)
With code LE5 (Ambient lighting with 64 colors in Marco Polo, assembly)
Rear seat monitoring control unit (N191) -

Ground connection

The "Terminal 31" ground connection is made over the right D-pillar ground point (W29/10).

Power supply

The power supply for "Terminal 30t" is implemented through the firewall fuse and relay module (K40/11).