Q5 Climate Control Panel Dead, HVAC System Failure

Having experienced this exact issue on a 2015 Audi Q3 2.0 TFSI, the symptoms point strongly to a wiring harness fault in the climate control system. The complete failure of the climate control panel combined with both heating and air conditioning issues typically indicates an electrical problem rather than a mechanical one. The root cause was damaged electrical connectors between the climate control module and the main wiring harness. The temperature sensor connections had corroded over time, leading to intermittent communication failures. The system stored fault codes related to the climate control communication network. The repair required replacing the main climate control wiring harness and electrical connectors. The job was fairly complex since accessing the harness meant removing several interior trim pieces and dashboard components. This is considered a serious repair due to the extensive disassembly required and the precision needed when working with electrical systems. When diagnosed properly, the temperature sensor readings should be verified before replacing any major components. A proper diagnostic scan will show if the climate control module is receiving correct signals from various system inputs. If your symptoms match these, having the electrical system properly diagnosed by a qualified technician who specializes in automotive electrical systems would be the recommended first step.

I had very similar issues with my Q5 last winter. The climate control panel was completely dead and the system would not respond at all. In my case it turned out to be the power supply unit that feeds the climate control module, a fairly common failure point according to the technician. The temperature sensor was also showing incorrect readings due to the electronic faults. The fix actually wasnt as complex as first feared, since they didnt need to replace the entire blower motor assembly. Theyaged to isolate the issue to just the power supply component. Did yours get resolved? Would be helpful to know what the final repair cost was in your case and if youve had any recurring issues since the fix? These electronic gremlins can sometimes come back, so Im curious if the solution was permanent.

After getting it properly diagnosed and fixed at the mechanic, Im happy to report the HVAC system is working perfectly now. The climate control panel came back to life and all functions are responding normally. The issue was indeed electrical, they found a damaged cable connection at the control module that was causing the power supply interruption. Much simpler fix than initially expected. Total repair cost was 95 Euro for replacing the faulty connector and testing the system. No recurring electronic faults since the repair was done. The blower motor, AC, and heating are all functioning as they should. Sometimes these electrical gremlins really just come down to basic connection issues rather than major component failures. Worth noting that proper diagnosis by a qualified tech who knows these electronic systems is key. They were able to pinpoint the exact connection causing the fault rather than replacing parts unnecessarily.

Thanks for sharing your experience. I finally got my car fixed last week after finding a shop specializing in automotive electrical systems. The mechanic found corroded electrical connectors affecting the HVAC system, similar to what others mentioned. The repair was straightforward, they cleaned and replaced the damaged connectors and tested all temperature sensor connections. Total cost came to 180 Euro including diagnostic time. Much better than the 800 Euro quote I got from my previous mechanic who wanted to replace the entire climate control module. The air conditioning now blows ice cold and the heating works perfectly. All climate control panel functions are responding normally. Really glad I asked here first and knew what to expect. Saved me from an unnecessary expensive repair.