Crown Vic Aux Heater Error

I had something similar with my Crown Vic. The parking heater refusing to activate and a stored error points towards the glow plug being the culprit. Have you checked the heat control or maybe the ventilation system? A faulty blower motor can also cause problems with heat control.

Heat control seems fine, ventilation strong. Blower motor works. Just no aux heat. Was your issue definitely the glow plug, or something else?

Pretty sure it was the glow plug. Symptoms sound identical. Unless you're a wizard with a multimeter, I'd get it to a workshop. Better safe than sorry with heater cores and potential coolant leaks.

Cheers. Shop confirmed glow plug. 440€ Sorted.