Insignia Immobilizer Issue

Sounds familiar! I've got an Insignia myself. Those symptoms scream immobilizer to me. Is the anti-theft system light behaving strangely when you try to start it? Have you tried your spare key, just to rule out a faulty transponder in the main key?

Thanks for the quick reply! The anti-theft light does flash a bit erratically. I haven't actually tried the spare key yet – I completely forgot I had one! If the spare key works, does that definitely point to a problem with the original key's programming, or could it still be something more complex?

If the spare key works, then it’s highly probable that your original key's programming is incorrect, although there are some exceptions. The best thing you can do is take it to a professional who can diagnose it, because it could be a faulty transponder in the key but also ignition control problems. A workshop can provide more clarity and ensure the anti-theft system is properly working.

Thanks a lot for the advice! I tried the spare key, and the car started right up. Took the original key to a workshop, and it turned out the programming was off. They reprogrammed it for 45€, and now it's working perfectly again!