Using a Taillight Converter to Wire a 2008 Chevy Uplander for a European 7-Way Trailer Connector

Question:

I live in Sweden and have recently purchased a Chevrolet Uplander 2008 with no trailer hitch. I want to install a trailer hitch using the trailer harness that came with the car, GM P/N 15871948 with wiring: - Red/white, Power always hot - Dark green, Right tum/stop - Yellow, Left turn/stop - Brown, Park/tail - Black, Ground and connect the harness to a European 7-pin trailer connector Type 12N ISO 1724 using the 118158 converter with the suggested wiring diagram in the etrailer Q/A Wiring US 4-Pole Trailer Connector to For Trailer with European 7-way. I have 2 questions: 1. 6 diodes are suggested to be used with the 118158 converter, but they are not included in the wiring diagram for trailer with European 7-way, why not? 2. Will the Stop lights be lit continously when braking and turning at the same time with either of the Turn signals blinking?

asked by: Per L

Expert Reply:

There are 2 ways you can tow the European trailer with a US 4-Way flat connector. You will either need to change the connector on the vehicle or change the connector on the trailer. Depending on which one you choose the converter # 118158 will either be on the vehicle side or the trailer side. No diodes are needed.

1). With your current setup, you will not need any diodes. The intended purpose of the diodes when used in conjunction with the taillight converter # 118158 is for a flat towing setup. The diodes prevent signal feedback to both your towed vehicle and the RV electrical systems.

On your European 7-way style trailer, both stop and turn lights will be activated when the function is active on your vehicle and the lights will be lit appropriately on your trailer.

What you will need to do is use the current GM specific part number 15871948 connector (indicates a combined taillight system), and cut off the 4-way trailer side connector.

Then you need to splice the converter # 118158 by connecting the appropriate wires on the input side of the converter to the GM part number 15871948. The running light circuit will bypass the # 118158 converter entirely, since it does not need to be converted. The converter # 118158 output will then connect to the European 7-way part number 12N ISO 1724 that you referenced. Providing a fully functional separate European 7-way connection from your 2008 Chevy Uplander to your trailer.

2). You will need a vehicle to vehicle tail light converter, part # 118158, which will separate the turn signal circuit from the brake light circuit. On the input side of the converter, you will attach the right turn/ brake circuit to the green wire, the left turn/ brake circuit to the yellow wire and the white wire will ground to ground wire from the trailer connector that is grounded to the trailer frame. The running light circuit will bypass the converter entirely, since it does not need to be converted.

On the output side, the yellow wire connects to the lead for the amber turn signal lamp on the drivers side, and the green wire connects to the lead for the amber turn signal lamp on the passenger side. The red wire is spliced to each side of the trailer and connects to the red stoplight lamp wires, and the brown wire that bypassed the converter is spliced to each side of the trailer and connected to the running light lamp wires.

To complete your trailer wiring you will also need a 4-Way trailer side connector, like part # 18004. I attached a diagram that shows how the converter should be wired to the trailer lights.

I have included a couple videos for you too.