1999 corsa 1.0

I would try disconnecting and reconnecting the battery. Maybe leave it off for a few mins.

You sure the battery has a full charge ? Once flat they're seldom the same again, is it the original battery or a replacement ?

its the same battery and it turns the engine fine, but because of the flashing management light no start

I'd say try a new battery, watch that engine light disappear. I had exactly the same problem

thanks will try tomorrow

I agree. On cranking, battery output is probably dipping below a level the ECU feel comfortable with and it's going into "jam it's thumb into its mouth mode".

PDH

tried heavy duty battery off work van, still same.

Did it work?

no still the same

Going to need to borrow a fault reader now.

Flashing while cranking usually means immobiliser problem. You'll need to get it to Vauxhall to diagnose it.

doesnt have an immobilisor

It does - it's just that it doesn't immobilise. Not as silly as it may sound, as the immobiliser is possibly more properly called the Engine Control Unit.

On most recent cars, this, as it adds zero cost to it to do so, also handles immobiliser functions.

The ECU is a little computer, that controls fuel/air mixture, when to inject the fuel, ...

re immobilisor, sorry mixed messages, yeah i know the fault is with the ecu, just strange it happened after the battery went flat, its never been a problem before, had a few cavaliers that the light has came on now and then but its never been a problem on the corsa till the battery problem,