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!
Featured Help Information
Miscellaneous Media
Continue Researching
- Shop: Trailer Wiring
- Search Results: trailer hitch
- Search Results: trailer wiring
- Q&A: Trying to Install ZCI Circuit Protected Vehicle Wiring Harness on 2023 Audi Q7 with 5 Wires
- Shop: Towing Kit w/ Ball Mount and Trailer Wiring for Stealth Hitches Hidden Rack Receiver - 2" Ball
- Shop: Hook Probe Circuit Tester
- Shop: Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector
- Video: Stealth Hitches Towing Kit with Ball Mount and Trailer Wiring Installation - 2017 Audi Q7
- Video: Tekonsha ZCI Circuit Protected Vehicle Wiring Harness Installation - 2018 Audi Q7
- Video: Mount: Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector on a 2008 Audi Q7
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Q&A: What is the Difference Between a 4-Way and 7-Way Trailer Connector
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Article: Trailer Wiring Diagrams
- Q&A: Trailer Hitch and Wiring that Fits 2021 Audi Q5 PHEV
- Article: Wiring Trailer Lights with a 4-Way Plug (It's Easier Than You Think)
- Article: How to Choose the Right Trailer Hitch Class
- Q&A: Will The Tekonsha 119250KIT Work On A 2021 Audi Q5 Hybrid
- Q&A: Recommended Trailer Hitch and Wiring for 2025 Audi Q5 PHEV
- Q&A: Does the etrailer Hitch e94CR Fit the 2023 Audi Q5 PHEV?
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Article: How to Measure for Trailer Hitch Drop
- Article: My Trailer Hitch Doesn't Fit
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.