OK when you use the red key the first flashes indicate how many keys are coded including the master(red) so three flashes would show three coded keys then your single flash is the error as per the black key
a single flash is -no serial line (connection between Immobiliser/CPU)

Cheers Bolds that explains the differences and also shows that the ley reader bit is working. Will check connections to ECU etc next and see if that uncovers anything

Bloody electronics eh! ... now with a magneto and a packed of fag papers you knew where you were - stuck in a lay-by in the ****ing rain most like!!