VW Sharan Aux Heater Failure: Causes and Solutions

Having some experience with diesel engines, I encountered a similar issue with my VW Touran 2012 diesel. The auxiliary heater stopped working during winter, and the blower motor showed no signs of life. After taking it to the workshop, they diagnosed a defective glow plug in the auxiliary heater. The temperature sensor was working fine, but the glow plug failure prevented the heating system from starting properly. The total repair cost was 440€, including parts and labor. The mechanic explained that glow plug issues are relatively common in these heating systems, especially after extended use. The repair process involved: Complete system diagnosis, Removing the auxiliary heater unit, Replacing the faulty glow plug, Testing the entire heating system functionality To provide more specific advice for your case, it would help to know: Current mileage on your Sharan, When the auxiliary heater was last serviced, Whether you notice any unusual sounds from the ventilation system, If the main heating system works normally, What specific error code your diagnostic system shows

Last service was 3 months ago at 14790km. After reading your response about the glow plug, I checked my service records. The climate control warning light occasionally flickers before the heating system fails completely. I already replaced the cabin temperature sensor last year, which worked fine until now. The main heat control works normally, but I noticed a slight buzzing sound from the auxiliary unit before it stopped working. The error code P2463 keeps showing up. Just wondering if this matches the symptoms you encountered with the glow plug issue, or if I should look into other potential causes.

Based on your description, the symptoms differ slightly from what I experienced with my Touran. While glow plug failure was my issue, your error code P2463 typically relates to the particulate filter system, which could indirectly affect the heater core and auxiliary heating system performance. The buzzing sound you mentioned was not present in my case. This noise, combined with the flickering climate control light, suggests a possible electrical issue in the heat control circuit or a failing auxiliary heater control module. Since your main heating system works properly, I would focus on the auxiliary unit connections and wiring before assuming its a glow plug problem. In my repair experience, intermittent electrical issues often preceded complete auxiliary heater failure. Some points to consider: Check the fuse box for any blown fuses related to the auxiliary heater, Have the battery voltage tested, as low voltage can cause heating system malfunctions, Monitor the temperature sensor readings through a diagnostic tool, Get the particulate filter checked due to the P2463 code My repair cost of 440€ might not be relevant in your case since the symptoms point to a different root cause. Consider getting a specialized diagnostic before replacing parts, as electrical issues often require different solutions than mechanical failures.

The buzzing noise from the auxiliary unit definitely seems like an important clue. Unlike your case with the Touran, my situation appears more complex with the P2463 code and potential electrical issues affecting the ventilation system. Your experience makes me realize I need to focus on the complete heating system diagnosis rather than just assuming its a glow plug problem. I will have the auxiliary heater electrical connections checked first, along with the particulate filter since that error code keeps appearing. I appreciate the detailed breakdown of possible issues. The fact that my main heat control works normally while only the auxiliary heating system fails does suggest a different problem than what you encountered. I will get the battery and fuses checked before proceeding with any major repairs. Will schedule a proper diagnostic test tomorrow and have them specifically look at the control module and wiring. The warning light behavior and buzzing sound really point toward an electrical problem in the heating system rather than a mechanical failure. Thanks for helping me narrow down the potential causes.