Taurus auxiliary heater malfunction

Sounds familiar! I had a similar issue with my old BMW 5 series, though it was a diesel. Auxiliary heater problems can be a pain. Did you check for any coolant leaks near the heater core? Sometimes a small leak can cause air pockets. Have you also scanned the climate control module for specific error codes beyond the generic 'heater malfunction'?

Good call on the coolant leak, I'll double-check. I only got a generic error code. Where is the climate control module located? Can I access the error codes with a standard OBD2 scanner, or do I need something more specialized?

The climate control module is usually behind the center console. Accessing the codes might require a scanner that can read manufacturer-specific codes, not just the standard OBD2 ones. If the glow plug checks out, it's probably best to bring it to a workshop to get a proper diagnosis. They'll have the right tools and expertise.

Thanks for the advice! I appreciate the insight. I took it to my local mechanic, and you were spot on. It was indeed a defective glow plug in the auxiliary heater. Cost me 440€ to get it sorted. At least the Taurus is toasty warm again.