FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Intermittent Trailer Lighting



Intermittent Trailer Lighting

Cause
When using a trailer with a 7-pin connector connected according to one of the following alternatives
- all exterior lighting is connected to either pin 5 or 7 in the 7-pin connector
- extra power consumers (e.g. heating fan) are connected via the trailer's connections for lighting (pin 5 or 7 in the 7-pin connector)

the load becomes too high in the car's REC and in the electronic module for the trailer. This results in the electronics switching on and off which means that the trailer lighting is intermittent.

Procedure

Alternative 1 (recommended)
Replace the trailer's connector and wiring harness with the 13-pin version. Extra power consumers are then connected to pin 9 or pin 10.

IMPORTANT: If connected to pin 9, the car's battery could be drained if the trailer is connected to the car and the car is not driven.


Pin No. 1-13:






Alternative 2
Make an adapter harness with a 7-pin female contact for connection to the trailer's connector at one end and a 13-pin male contact for connection to the car's connector at the other end. The connectors are connected together as follows:

IMPORTANT: A rear fog lamp (if fitted) cannot be used on the trailer. If connected to pin 9, the car's battery could be drained if the trailer is connected to the car and the car is not driven.


Pin No. 1-7: