P38A Engine immobilised - Press remote

A while back I had trouble when my battery flattened-alarm at 2:30 a.m., EKA impossible etc. (See my other thread if you want a laugh)
I've replaced the battery with 1000CCA , moved the P38 across my driveway (in case it was picking up spurious signals from my neighbour) and unplugged the blue aerial wire from the RF receiver.
When I replaced the battery, everything returned to normal
EXCEPT
When I unlock the car (not super locked) the doors unlock, but usually (not ALWAYS) I get "engine immobilised-press remote"
Because I've unplugged the aerial, I have to turn off, remove key, and press the remote over my shoulder near the receiver. There's a clunk from the locks, and the car will start fine.
I've read all the threads which suggest door or tailgate locks, but they work fine. There's no requirement for EKA access.
Is it the RF aerial unplug that needs re-connecting? Remote battery? Help!

Could well be. Read the security bit in RAVE. I'm struggling to remember but there is a rolling code that get incremented each time you blip it and then this code is transmitted to the fob. With the RF receiver out the loop the key will go out of sync. If you have a later model the key will resync when you put the key in the ignition barrel.

Are you locking the car with the remote then opening it with the key?

Re-connect the RF aerial if your car is one of the later models with the transponder coil round the ignition barrel (LED blinks on FOB when putting key in ignition)

wammers said:

Are you locking the car with the remote then opening it with the key?

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Nope. Just zap it near the receiver window.

Datatek said:

Re-connect the RF aerial if your car is one of the later models with the transponder coil round the ignition barrel (LED blinks on FOB when putting key in ignition)

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I'll look at this tomorrow. I haven't looked to see if it blinks in the ignition

Grrrrrr said:

With the RF receiver out the loop the key will go out of sync.

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I may just try to reconnect the RF aerial as it might be the easier fix. I disconnected it "just in case"
Thanks for all these bits of help.

ibgarrow said:

Nope. Just zap it near the receiver window.

I'll look at this tomorrow. I haven't looked to see if it blinks in the ignition

I may just try to reconnect the RF aerial as it might be the easier fix. I disconnected it "just in case"
Thanks for all these bits of help.

Click to expand...

Do Brian's second fob trick. I tried disconnecting mine after it lost sync a few times. I went through 3 lots of locks before I bit the bullet and bought the new receiver unit. Not a single issue since. Having forked out £150 @brianp38dse came up with his £5 second fob trick which rubbed the salt in a bit. Mind you, the same unit are now well over £200 so feel lucky from that perspective.

Aye, the second fob "Jog-Unit" is a masterstroke. Grateful thanks to @brianp38dse for that one.
Luckily, I seem to have no burnt-out locks so-far.

Here is the thread if you wish to save your self a few quid that can then be spent on other things for the range rover

https://www.landyzone.co.uk/land-rover/rf-reciever-work-round.258096/