Eseries preheating lamp and check engine light

Sounds familiar! My old Opel Astra had the preheating light stuck on and the engine felt choked on acceleration. It was a dodgy connection to the glow plug relay. Did you check the voltage at the glow plugs?

I haven't checked the voltage at the glow plugs. Could you explain how to test the voltage and what readings would indicate a fault?

Messing with a diesel's electrical system can be risky. I'd recommend a workshop. They can diagnose it properly and replace the control unit if needed. Better than frying something and getting a bigger bill!

Thanks for the guidance. Given the potential complications, I'll consult a qualified technician. It's best to leave this to professionals. The repair set me back 95€.