Vauxhall Vectra Auxiliary Heater Problem

I had a similar issue with my Vectra. Have you checked the blower motor and the related fuses? A faulty blower motor can sometimes prevent the auxiliary heater from starting. Also, does the main car heater work without any issues? It might be related to the heater core.

Thanks. The main car heater works fine. Are you saying that even with the primary heating system working, a partially defective blower motor could still stop the auxiliary heater, even if it doesn't affect the main car heating? How would that show up in the error memory?

Yes, that's right. In my case, the main heater was fine, but the auxiliary heater wouldn't kick in. The error memory can be vague, not directly pointing to the blower motor. Given the cost of diagnosing this yourself, I'd advise taking it to a workshop to get it checked. The glow plug could be the reason, but that's just guesswork without a proper diagnosis.

Thanks for the guidance. I went to a workshop, and it was a defective glow plug, like you suspected. The repair cost 440€. Your insights were invaluable in fixing this.