Lights on dash help

[Tomsta79]

Hi there could some one please help me with this . Lights come on dash and car will not start I've had*instrument cluster repaired thought it was that I've put new ecu on it thinking it might of been a bad ecu . Light what are on is airbag abs and*traction control light it cranks but does not start* this is going to sound daft but when I bang ecu box under bonnet all lights come on as they should and car fires up I've checked relays no dampness are any thing could it still be a relay going bad can't get me head around why this is happening*

[pdlh]

Sounds a bit like an immobiliser issue I had with my old B6 many years ago, touch wood it seems to have sorted itself out, but a couple of times I came out to the car and it had reset itself, all the lights came on but the engine would not start.

Have you tried a reset of the car, e.g. battery disconnected for 10 minutes or longer?

It does sound a bit like immobiliser, does the key need to be syncronised with the car again?