Mobile Auto Locksmith
Immobiliser Problems
The immobiliser is the vehicle's built-in anti-theft system. It checks the key's transponder every time you try to start, and if the exchange fails the engine is blocked — often with a flashing warning light on the dash and a car that turns over but never fires.
We diagnose the key and immobiliser side of that failure and program keys where that is the cause.
- Immobiliser faults and warning lights
- Key recognised incorrectly or intermittently
- Vehicle cranking but refusing to start
- Key and immobiliser programming
- Immobiliser diagnosis
- Advice on next steps where the fault is not key-related
Common causes
A failed transponder in the key, a damaged aerial ring around the ignition barrel, low battery voltage or wiring damage are all common. Immobiliser symptoms can also appear after a battery change or a jump start.
What we can and cannot promise
We do not guarantee a fix before seeing the vehicle. Immobiliser faults can sit in the key, the reader, the wiring or the engine control unit. We diagnose, tell you what we find, and carry out the key or programming work where that is the answer.
Try the spare key first
If you have a second key, try it. If the car starts on the spare, the problem is almost certainly the first key.
Immobiliser Problems FAQs
My immobiliser light is flashing and the car won't start — can you help?
We can diagnose the key and immobiliser side of the problem and carry out key or programming work where that is the cause. We do not promise a fix before inspecting the vehicle.
It started happening after a flat battery — is that related?
It can be. Low voltage during starting can cause immobiliser communication failures.
Will a new key definitely solve it?
Only if the key is the fault. That is exactly what diagnosis is for, and we will not sell you a key that will not fix the problem.
Get Immobiliser Help
Only Car Key provides mobile car key replacement, spare keys, vehicle unlocking and key programming across East London, Essex and surrounding areas.
For vehicle security, proof of ownership or authority to access the vehicle may be requested before locksmith work is carried out.