how do i reset a vauxhall omega immobiliser?

Sorry, Mine was the same and it cannot be reset by the owner. It must be reset by using either a Tech1 or Tech2 machine at a dealership or by a garage that has one. Even then it is not so simple as you also need the data from the Pass Card for the vehicle for them to be able to reset it. I eventually had mine repaired by replacing the Immobiser unit which came with the relevant transponders.
Good luck anyway
Ray

Raymond J Watson
May 2008