Typical garage response. I'm still VERY suspect of their comments.
Symptoms of the main ECU cutting/not working out are rough running and funny things happening to the water temperature meter. Similarly, the pre-heat light doesn't come on although, when the van is hot, you can restart and drive it anyway (albeit with a rough 'diesel' sounding noise). The van WILL start and run (roughly but no damage to the engine) if you do the following.
If you can't get pre-heat light to come on you can short the pre-heat relay terminals (the ones with the big fat wires on) for 10 seconds to give the van a chance to start. If it does then look at the double relay (left hand side of compartment as viewed from the front) as it's THIS relay that provides the power to the ECU and is a common cause of faults.
A new double relay costs about £14. The ECU????? Gawd forbid..... but an easy money-making exercise for the garage.
If you're feeling adventurous and suspect the double relay IS the fault then hack it apart and clean the contacts as a stop-gap solution (it works - I've done it and I'm still on the road after 2 months).
Anyway..... a 'cut wire' or fault in the loom does NOT make the ECU go "t i ts-up". What kind of idiot (garage) jumps straight to THIS assumption?
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