Troubleshooting Lights Failing After Installation of Curt 59236 on 2010 Audi Q5
Question:
I have installed two of the 59236 on my Audi 2010 Q5, and have experienced the same problem with both units. All tests well, all functions well - until you start the car. The left and right turn signals slowly start to function intermittently, then fail altogether, about a minue or two after starting. Same with the brake lights. I can say it is definitely not the ground as I doubled up to the vehicle just in case. There is plenty of power going to the unit, even when I start the car and the lights start to flicker and die. All connections are solid and tested. I am done with my troubleshooting, it beat me! Anybody?
asked by: Peter V
Expert Reply:
It sounds like you have checked everything following your # C59236. A single harness failure happens sometimes but two in a row is not something we really see. The only thing I can think of is checking the power source. Make sure you are in fact hooked up to the vehicle battery.
Outside of that, I can only recommend using the Tekonsha Upgraded Heavy Duty ModuLite Circuit Protected Vehicle Wiring Harness # 119250KIT instead. Tekonsha is the most reliable when it comes to wiring so if it is actually the Curt wiring harness failing you can expect the Tekonsha to work.
I attached an installation video for the Tekonsha harness on a 2012 Q5 below for your reference. It is probably worth looking at to see if you missed anything during the installation since it is the same process for the Curt.

Products Referenced in This Question
ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Converter
- Universal Fit
- 4 Flat
- Tekonsha
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Product Page this Question was Asked From
Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Converter
- Universal Fit
- 4 Flat
- CURT
more information >
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