Immobiliser problems

[mark smith87]

I've just had a fault with my 172 refusing to start. The red light on the dash was flashing fast every time the ignition was switched on. I called the AA out and they managed to get it running so I took it straight to Birchdown. As soon as I turned the engine off the fault came back again. They called out an auto electrician and he upgraded the transponders in the keys. This seemed to sort the fault for a few hours but when I went to collect the car the fault came back while I was at Birchdown. So I left the car with them again for a couple of days while they did some investigation. They found a spare code reader ring that fits on the ignition switch and swapped it with the one on the car. Amazingly that sorted it. Problem solved. So it appears that the code reader ring can fail and arm the immobiliser.
I would suggest trying this as a first line of thought if anyone has the same fault.
A huge thanks to Andy and Steve at Birchdown for all their help.

 

[Dan_Arctic182]

I've got the same problem but the light isn't flashing, just won't start. This happened a few months ago so I tried my spare key and it's been ok since except last night. I've read that if I turn the ignition 2 clicks for 30 seconds then turn off, and on again for 30 seconds it might work, but the car isn't at home so I can't try it.

Also when I do try to start it, get out and lock the car, the hazard lights flash but the central locking doesn't work, I have to unlock it then lock again it for it to work.

 

[royz]

mark was this a intermintant problem or all the time.
thanks