Hello all,
long time listener, first time poster,
"Engine disabled, press fob" on dash -> I press fob "start engine" -> engine starts fine,
happens irregularly, more often than not, however not every start.. never any other issues, engine always starts.. started happening a few months ago now..
wondering if anyone knows any causes? issues? fixes? Just gets rather annoying!
vehicle is 2001 p38 4.0l
Thank-you for your help
Chris

It's caused when passive immobilisation is enabled and you take your time. If you unlock the car but don't start it within a set time (either 30 or 60 seconds, I don't remember), the immobiliser kicks in again. There is a coil around the ignition switch that causes the key to automatically send the unlock code to turn the immobiliser off as soon as you put the key in the ignition (if you look at it you'll see the LED on the fob flash). This coil is very fragile so can fail meaning the unlock code isn't sent so you need to press the button on the fob to turn the immobiliser off.

So, if you unlock the car, put the key in the ignition but don't start it within the set time, the immobiliser will kick in again. If the col has failed, you put the key in but don't start it, the same happens. If you unlock it and still don't start within the set time, it kicks in again.

Easiest fix if you have access to a Nanocom (or someone that has one) is to turn off Passive Immobilisation. That way you can unlock it and it doesn't matter how long you leave it, the immobiliser won't kick in until the next time you lock it. Where are you, there may be someone nearby with a Nanocom, it only takes about a minute.

OK, thanks cheers for your answer. Was just reading about passive immbolisation, (it is 30 seconds time-out)
Am up near Luton.
Thanks again.

I'm near Peterborough but have to go to Maulden on Thursday or Friday this week, so could call in and turn it off for you.