Peugeot Boxer Glow Plug Issue

The symptoms you describe, specifically the persistent preheating lamp and stored error, strongly suggest a glow plug issue. Have you noticed any difficulty starting the engine, particularly in cold weather? How old are the glow plugs?

Cold starts are definitely rougher than they used to be, now that you mention it. As for the glow plugs, I'm not actually sure when they were last changed. Is there any way to confirm the defective glow plug without pulling everything apart?

Given the starting difficulty and the electrical fault, it is highly probable a glow plug has failed. While diagnostic tools can sometimes pinpoint the faulty plug, physical inspection is often necessary. Considering the potential complexity and specialized tools required, and potential repair costs around 440€, I recommend taking your Peugeot Boxer to a qualified workshop.

Thanks for the advice. I took it to a workshop, and they confirmed it was indeed a defective glow plug. They replaced all four. Appreciate the help!