Audi Q5 Random Headlight Issues Fixed, Owner's Guide

As someone with some experience working on cars, I had a similar issue with my 2020 Audi Q3. The headlight switch started acting up in a comparable way, with unusual activation and dimmer control problems. After checking the car lighting system, my workshop found that the main headlight switch wiring connection had deteriorated. The issue was causing intermittent electrical contact, leading to the unusual activation you described. The automotive switch assembly itself was fine, but the connector pins were corroded. The repair involved cleaning the connections and replacing the damaged wiring section near the switch. Total cost was 95 Euro for parts and labor. The whole process took about an hour, and the problem hasnt returned since. Before jumping to conclusions about your Q5, it would help to know: Are there any specific error codes stored? Does the issue occur more frequently when its cold or wet? Have you noticed any other electrical issues, like dashboard flickering? Did you check the fuse box for any blown fuses? These details would help determine if youre dealing with the same connector issue or if its something else in the car switch system.

Thanks for the insights. My Q5 just hit 141361 KM and had its last service 4 months ago. The dashboard lights start flickering before the headlights act up, and the dimmer switch becomes unresponsive. The error codes point to a fault in the lighting control module. The tail lights seem fine, but the automatic headlight function is completely unpredictable. The issue definitely gets worse during wet weather. Already checked the fuse box, all fuses related to lighting are intact. The dealer quoted 450 Euro for diagnostics and potential switch assembly replacement. Looking for more affordable options since the car is out of warranty.

Thanks for providing those additional details about your Q5. Your symptoms sound nearly identical to what I experienced, especially the correlation with wet weather and dashboard flickering. In my case, the initial quote for a complete switch assembly replacement was also around 400 Euro, but the actual issue turned out to be much simpler. The moisture sensitivity and flickering dashboard are classic signs of corroded connections, just like what I dealt with on my Q3. A thorough inspection revealed that water had seeped into the wiring harness connecting the automotive switch to the lighting control module. This created oxidation on the connector pins, causing intermittent electrical problems with both the headlights and dimmer switch functions. The tail lights working properly actually helped confirm this diagnosis, as they operate on a separate circuit. If you have a trusted local workshop, they should be able to clean and repair the connections for much less than the dealer quote. Given the similar behavior in wet conditions, I strongly suspect youre dealing with the same wiring harness issue rather than a faulty light switch or complete module failure. My repair has held up perfectly for over a year now, even in heavy rain. Consider getting a second opinion from an independent shop that specializes in electrical problems. They might be able to fix it for around 100-150 Euro instead of the full switch replacement the dealer suggests.

The repair workshop I visited last week confirmed it was indeed a wiring harness issue, just as you described. They found corrosion in the connections between the light switch and control module, matching exactly what you experienced with your Q3. The total repair cost came to 135 Euro, which included cleaning the connections, applying dielectric grease, and replacing a small section of damaged wiring. Much more reasonable than the dealer quote. The car lighting system is now working perfectly, no more unusual headlight activation or dimmer switch problems. The dashboard has stopped flickering too. The automatic headlight function is back to normal, and the electrical problem hasnt returned even during recent rainy weather. Really appreciate your detailed explanation that helped me avoid an unnecessary and expensive switch assembly replacement. Will definitely keep an eye on these connections during future services to prevent similar issues.