VW Sharan HVAC System Complete Failure & Diagnosis Tips

Having worked on several VW models, I encountered a very similar issue with my 2012 VW Touran diesel. The symptoms were nearly identical, particularly with the unresponsive climate control and heating problems. After multiple error codes appeared, the workshop diagnosed the root cause as faulty electrical connectors in the wiring harness connecting to the climate control unit. The connection had deteriorated over time, causing intermittent failures in both heating and AC functions. The blower motor was tested and found to be working correctly, the issue was purely with the electrical connections. The repair involved: Testing the control panel functionality, Inspecting the complete wiring harness, Replacing damaged electrical connectors, Recalibrating the climate control system Total cost was 95€ including parts and labor. Since the repair, all climate control functions have worked perfectly. To better assist with your specific case, could you share: Which exact error codes are showing? Does the blower motor run at any speed? Are there any clicking sounds when adjusting temperature? Have you noticed any electrical issues with other dashboard controls? This information would help determine if your issue matches what I experienced with the faulty connectors.

Last serviced at 31501km and can confirm similar symptoms, though my power supply issues seemed more severe. After checking the control panel thoroughly, found several dead zones where buttons wouldnt register at all. The electronic faults showed up consistently on cold starts. The wiring harness inspection revealed significant wear near the main connection points. My climate control module needed a full replacement, which also resolved some other electrical gremlins affecting the dashboard displays. Final repair cost was 320€ with parts and labor. Workshop confirmed this is a known issue on these models, typically appearing between 30000-40000km.

Thanks for the additional details about your service history. The symptoms you describe with the dead zones on the control panel and cold start issues actually mirror my experience even more closely than I initially thought. After my initial wiring harness repair, I also ended up needing a complete climate control module replacement just like you. The HVAC system would act erratically especially during cold weather, and sections of the control panel became completely unresponsive. The power supply issues were definitely affecting other dashboard functions too. The workshop found that while the damaged connectors contributed to the problem, the root cause was indeed a failing climate control module. Once replaced, it resolved both the heating output issues and restored proper air conditioning function. The blower motor and other components tested fine after the new module was installed. The 320€ repair cost matches the typical range for this fix. Since having the module replaced, all climate control functions have worked flawlessly for over 25000km now. The improved electrical connections also eliminated those dashboard display glitches. Would recommend others experiencing similar symptoms to have both the wiring harness and control module checked, as these often fail as a pair on these models.

Thanks for sharing those repair details. The electronic faults I experienced became worse over time, exactly as you described. My blower motor would out of nowhere stop working, especially during the first few minutes after starting the car. The power supply to the climate control unit was definitely compromised based on how the panel would flicker and become unresponsive. My air conditioning issues turned out to be connected to the same electrical connectors problem you mentioned. The workshop found significant corrosion on several connection points. Good call on suggesting checking both the wiring harness and control module together, wish I had done that initially instead of having two separate repairs. The 320€ total cost seems standard for this type of fix. Since having both components replaced, the heating works perfectly and the air conditioning runs without any issues. No more problems with the electrical connectors or climate control panel. The investment was worth it to have a properly functioning system again.