How to Find Correct Wires for Installing Tekonsha ZCI Wiring on a 2021 Audi Q7
Updated 09/02/2025 | Published 06/29/2025
Question:
Hi, I have a 2021 Q7. I followed the instructions imbedded in the purchasing link, they were great. Major kudos to your video crew. One issue I hit was the 2018 Audi in the video has 4 wires in on the right tail light, mine has 6. The car is currently full reassembled but when i hit the right turn signal, the four ways come on. Everything else works fine. Are you able to provide a description or a diagram showing what all 6 wires do for a 21 Q7? I can’t locate online anywhere. I’m pretty sure I just have the right turn on the wrong wire, but not sure which one it goes on.
asked by: J B
Expert Reply:
Hey J, thanks for reaching out!
I'm glad you were able to figure out the instructions for the ZCI Circuit Protected Vehicle Wiring Harness # 119250KIT - most people get a bit overwhelmed.
I unfortunately don't have a wiring diagram that shows what the wires are on your 2021 Audi Q7. Were you able to use the included circuit tester to test what each wire did on your Q7? If it works, then you'll be able to use that to determine what wire carries which function.
You also could try reaching out to an Audi dealer to see if they're able to help out with that at all.
Let me know what you end up finding out, so we can have it posted for future readers to see!
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on Custom Fit Vehicle Wiring
Jon G.
9/2/2025
Hey J, Did you have any luck using the circuit tester to figure out the wiring on your Q7? I'm eager to hear what you discovered, as it could really help others facing the same issue.