Disco 2 Immobilizer question

Hello Guys
Hope you are doing fine!
Yesterday while I started the car strange thing happened. The car started normally but after 1-2 sec it sopped and I could not restart. I closed the car with key fob the opened and the car started. Can it be an immobilizer issue (I do not remember if the light was flashing or not)?
If yes is it key fob or other issue?
I have already changed my EKA to a simple one but never tried if it works. Can I test by using the spare key with battery removed (just to be sure if the immobilizer dies it will work)? If it will not work the car can still be started with the key with battery, right? I do not want to take any risk to immobilize my car.
Thanks

Hi, disable the passive immobiliser with tester and see then, it's possibe that the part in the fob which works with the remobilisation coil has failed then an unlock command is needed if you didnt start the engine within 30 seconds after you unlocked the vehicle though once started it should not stall so you might have some other problem

Thanks Fery. Also strange for me that it happened 2-3sec after I started the car. When I wanted to restart it seemed that fuel cut off as it cranked but did not started. After closing and opening it started fine. Since then (I started several times) no issue. It also happened in the past with my previous D2.
Regarding on passive immobilizer, is it worth to keep it alive or better to switch off as it only blocks the owner and probably not the thief...?

I disabled the passive coil on mine, it's a personal choice i can't comment. The thing that it stalled after it started can be a bad contact on the security link between the BCU and ECM as the ECM is loosing the security code ar that very moment, unless your ECU or BCU is on the way to a failure.
Immobilisation system
When the starter switch is turned on, the BCU sends a unique security code to the ECM. The ECM must accept this
code before it will allow the engine to operate. If the ECM receives no security code or the ECM receives the incorrect
security code, then the ECM allows the engine to run for 0.5 seconds only. During this operation all other ECM
functions remain as normal.

Eventually give some contact spray in the ECM black plug and BCU plugs cos that link is hardwired untill the BCU so no other connector involved

Fery, If that communication complatelly failes EKA still can be used for remobilizing?
If I switch off passive immobilizer can this problem be finally solved?
Thanks

Good question about the security line, i can only guess that if it fails EKA should still work but i'm not sure. I dont know exactly what was the issue with yours so disabbling the passive immobiliser will solve it only if the problem was on that path. All you can do is to try and see what happens

Ok, thanks.