Spacefox Window Heating System Failure Fix Needed

Having dealt with similar heating issues on my 2008 Sportfox with about the same build specs, I can share some relevant experience from my garage visits last winter. The auto defrost system completely failed on both windows. After checking the heating coil connections, the workshop found that a heavily discharged battery was the root cause. The thermal window system needs proper voltage to function, and a weak battery can cause both the rear defroster and windshield heating to malfunction. The repair included: Battery testing and replacement, Testing all window heater connections, Checking the relay system, Full system diagnostic scan Total cost was 290€ for parts and labor, with the battery being the main expense. The fix resolved both window issues completely. To help diagnose your specific case, could you share: Current battery age, Whether the heating issues started gradually or suddenly, If you notice any other electrical issues, Whether the problems occur more during cold starts These details would help determine if your issue matches what I experienced and whether you might be looking at a similar repair path.

Had my last service done 2 months ago at 87545km. After checking the workshop report, they didnt test the defroster system. The window heating issues appeared suddenly last week during a cold morning. No other electrical problems noticed. The battery is fairly new, replaced 8 months ago. The rear window heating still shows no response when activated, and the windshield demister now works intermittently. The workshop estimated 380€ for diagnostics and repairs, which seems steep compared to your battery-related fix. Already checked the fuses but all look fine. The heating relay clicks when switching the system on, so that part seems to work. Could there be a break in the heating elements themselves?

Thanks for those additional details. Given that your battery is relatively new and the relay is responding, your issue does seem different from what I encountered. The clicking relay and sudden onset suggest the thermal window system might have a different problem than what I faced. Based on the symptoms, the defroster repair could involve: A break in the heating elements themselves, Loose or corroded connections at the window edges, A faulty control module When my auto defrost problems were battery-related, the system showed more gradual decline and affected other electrical components. Your case showing sudden failure specifically in the window heater circuits points toward a different cause. The 380€ estimate might include replacing heating elements if broken, which would explain the higher cost compared to my battery fix. A simple test you can do is check for continuity across the heating lines using a multimeter, this helped identify where the break was in my previous car before the battery issue. If the windshield heating works intermittently while the rear defroster is completely dead, you might be dealing with two separate issues. Consider getting a second opinion since your symptoms differ from the battery-related problems I experienced.

Thanks for sharing such detailed repair experience with the defroster issues. After comparing your battery-related fix with my situation, I think I need to look beyond just the power supply since my battery is still fairly new. I will try testing the heating elements with a multimeter before committing to that 380€ repair quote. The clicking relay does suggest the control system works, so the thermal window elements themselves might be the culprit. Since the rear defroster is completely dead while the windshield heating still works sometimes, dealing with two separate issues makes sense. Will get another workshop opinion and have them specifically check the heating coil connections and elements. The auto defrost problems seem more complex than just a battery issue in my case. Really helpful to know what diagnostic steps were taken in your repair, gives me a better baseline for discussing options with the mechanics.