Troubleshooting Non-Functioning Brake Lights When Flat Towing A 2012 Jeep Grand Cherokee

Question:

We have a 2012 Jeep Grand Cherokee 4x4 with the appropriate transmission. Problem is that when the Jeep is ready to tow, in Park, and in the off position the brake lights do not come on. It looks like we have to leave the Jeep in the AUX position. Is there any downside to the Jeep when doing this or is there a better way to have brake lights?

asked by: Tim L

Expert Reply:

The first thing to ensure is that the transfer case is in Neutral and that the transmission is in park. If not then you can damage the components of your 2012 Jeep Grand Cherokee.

As for the wiring I recommend using a circuit tester like # PTW2993 to first test the functions on the trailer connector at the rear of the RV. Check to make sure all of the needed functions are providing a circuit, particularly the stop light function.

If the signal is coming through from the motorhome then you can trace the wires to through the vehicle to the tail lights using the test to find where the signal is being lost. It could just be that you got a bad diode wiring kit or that you have a loose connection somewhere.

The power from your motorhome is what actually powers the tail lights on your Jeep, so there's a break in the connection somewhere.

expert reply by: Kevin C