Audi A5 Seat Heater Failure: Dual Sensor Issue Fixed

Had similar seat heating problems with my 2015 Audi A6 last winter. The seat warmer stopped working completely in both front seats, despite the temperature control buttons lighting up normally. With some experience working on Audi electrical systems, I first checked the fuses, but they were fine. Took it to a workshop where they diagnosed faulty heating elements in both seat heating mats. The heating mats had developed breaks in the internal wiring, apparently a common issue in these models. The repair involved: Complete diagnostic scan, Removal of seat covers, Replacement of heating element mats, Installation of new temperature sensors, System testing and coding Total cost was 390 Euro for parts and labor. The seat heating works perfectly now with all temperature settings functioning as they should. To provide more specific guidance for your A5: What engine variant do you have? Are you getting any specific error codes? Does the heater failure happen at all temperature settings? Did the problem develop gradually or stop working suddenly?

Thanks for sharing your A6 experience. Following up on my case (63817 KM, last service 2 months ago): The heating failure occurred suddenly in both seats after working fine previously. All temperature control settings from 1-3 show no heating response, though indicator lights work normally. Error codes P0724 and P0725 appear consistently during diagnostics. I also suspect the heating elements rather than the controls, since both seats failed simultaneously. Before booking workshop time, I want to understand if replacing just the heating mats might solve it, versus needing the complete sensor assembly. Would be helpful to know the specific part numbers you had replaced in your repair. Was the temperature sensor replacement strictly necessary or more precautionary in your case?

Based on my A6 repair experience, simultaneous failure of both seat heating systems points strongly to heating element issues, especially with those error codes which typically indicate heating mat circuit problems. The heating element replacement was the core fix in my case. While the workshop initially suggested replacing the entire thermal sensor assembly, we found the temperature sensors themselves were actually functioning correctly. The heating mats were the only truly faulty components. The part numbers for my heating elements were 4G0963557B for the seat cushion and 4G0963558A for the backrest, though verify compatibility for your A5. Total parts cost around 220 Euro with labor making up the rest. A key diagnostic point: our temperature control system could still detect and display settings, but the heating elements simply weren't receiving proper current due to broken internal wiring in the seat heating mats. This matches your symptoms exactly. My suggestion would be to first have the heating elements tested individually. If the thermal sensor readings are normal but the heating elements show circuit breaks, you can likely save money by replacing just the heating mats rather than the complete assembly.

Thanks for the detailed info. This helps confirm my suspicions about the heating elements being the core issue. Those part numbers are really helpful, I checked and they're compatible with my A5 model. Given the matching symptoms and error codes, I feel more confident now about focusing on the heating mat replacement rather than the complete sensor assembly. The fact that your temperature sensors tested fine despite similar failure patterns is particularly relevant. I'll schedule the repair and have them test the heating elements first before replacing other components. The cost breakdown you provided helps set realistic expectations, I was worried it might be significantly more expensive if the entire temperature control system needed replacement. Quick follow-up on the seat heating repair process, did your workshop need to order the parts specifically, or were the heating mats typically kept in stock? Just trying to plan for potential repair timing and whether I should expect delays getting the parts.