Vauxhall combo van not starting

I had a similar vintage Astra which failed in a similar way, it turned out to be a dry solder joint on the power transistor in the second ECU thingy which lives between the engine and the rear bulkhead. A standard fault on that model apparently (sorry can't remember exact year or other details), good advice on Vauxhall owners forum on the web.

Forgive the daft question but would a fault like that have an error code? T he local tyre place reads codes for twenty quid and I can borrow a trailer. New ECUs look expensive and it would be embarrassing to send off the old E CU for repair only to find it did not need one.

Not a daft question at all. Yes, I think it did. Certainly worth getting the code read. I don't quite recall if it identifed that part correctly, IIRC it said ECU but didn't differentiate between the main box on top of the engine and the small one behind. MrC might know.

While I was agonising over whether to get the main ECU checked (there are firms which do reconditioned exchanges, but test your box too so it only costs return postage if your box is OK) I did a lot of googling. I found that the second box was a "known fault" which is easily identifiable (once you get it out, which is a PITA) because you can see the burned board after you take the lid off, and in that state it is still repairable by resoldering. So I tried that as the least cost option, and it worked.

Okay. I have been googling and it turns out with Combos of this era you can do a pedal test. You turn the key with the throttle and brake down and cou nt the flashes of the engine light to get an error code. In my case I am ge tting codes 0370 and 1631. After a bit more Googling I *think* they can rel ate to a couple of faults including the ECU for the fuel pump. Would this b e the same ECU that was faulty on yours?

Yes might well be. A few years ago so sorry can't recall the details. Certainly fuel related, IIRC.

It's a box about 5 x 4 x 1 inch. IIRC you could not remove the PCB from the box without unsoldering a number of contacts entering from beneath, but the failed joint was in the middle of the board and accessible once you got the lid off. The sort of thing which ideally you would disassemble and clean thoroughly before re-soldering, but this means disturbing much more. In the end it seemed to solder OK using a big iron and, I think, resin rather than acid flux. Illegal leaded solder for reliability, of course.

snipped-for-privacy@newsguy.com formulated the question :

Error codes are just a general clue as to the problem, they cannot be relied upon to be complaining about the correct failed component. They form a reasonable starting point for diagnosis.

With an internal failure of the ECU, possibly it might generate a code, but the code would be even less likely to point to the true issue.