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There may be some confusion here (which I may have added to above when we wre not sure of the YM) ?

As Frank's is a later model the re-syncing is done via the fob/ignition barrel coil combo... ie. not the earlier fob/receiver technique

-And LR used another misnomer for this too of course; " Friendly re-sychronisation " !!

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No dave, the only confusion here is being added by you. Syncing the fob is done using the key in the door on all model years. If you had read the ETM for a 99 model, you would see that this is the case and RFID is NOT used and the coil is there to turn off passive immobilisation as I described earlier. The only difference between pre and post 97 model cars is that not all of the early cars had the coil fitted.

See the relevant ETM page
enter image description here

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To be fair Richard I have read ETMs / Owners Manuals / Rave / other stuff ad nauseum and they are (too often) contradictory !

Incidentally I am referring to the coil/fob combo which uses 'RFID' techniques for, I agree, immobilisation purposes as in:

(Range Rover familiarisation documentation)
Operation: Disabling passive immobiliser

"The BeCM receives a signal from the ignition key input switch as soon as an ignition key is inserted. In response that this signal the BeCM will provide a pulse output signal to the inductive wire coil fitted around the top of the ignition switch. This coil will in turn induce a pulsed voltage signal to a smaller wire coil incorporated within the ignition key assembly. Circuitry, also housed within the ignition key assembly automatically responds to the induced voltage signal detected by the smaller coil, by activating a remote lock signal. Providing the remote lock signal received is recognised by the BeCM as an authorised signal it will automatically remove the crank inhibition and re-mobilise the electronic engine immobilisation without there being a need for the driver to take any further action"

Ok, that is all in LR-speak but it seems to be saying that you (ok, Frank...) has to insert the key into the ignition (which is recognised via RFID), and then the fob sends the RF signal to the BeCM via the receiver etc etc to remove the "Disabled" condition (?).

My main question then is if the key is not first recognised via the RFID/coil system, will (just) pressing the fob button be the same ?
Or, and repeating this in another way, will the BeCM wake up (and also remove immobilsation) if the key is not actually in the ignition ?

You seem to be saying that once Frank's key is re-synched (via the door lock technique via a working receiver...) all will be fine; Lets hope so !

It is easy to get re-synchronisation and immobilisation confused in this mire....although LR's terminology is far too often truly awful of course.....
As is frequently the case: It is written by "those who know/understand" for those who don't.....and often still don't after reading it umpteen times !!

EDIT: Just had a thought; but it won't help much: If the coil/RFID technique is called "friendly re-synchronisation"
should the (universal) 'waggle the key in the door lock' etc method now be called "less friendly synchronisation" ?
Or perhaps even "aquaintance re-sychronisation" ?
Never mind....

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Slight diversion but Frank also initially said he wanted to learn more about P38s......

Whilst I have that original (Brabyn) content from -the other side- I could send him (8Meg/.pdf) to help with this I can't find the original link there
(ie. the one where someone had compressed all Brabyn's helpful "Troubleshooting Tips" down to a single file)...

Anyone recall who posted this up over there ?

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davew wrote:

Ok, that is all in LR-speak but it seems to be saying that you (ok, Frank...) has to insert the key into the ignition (which is recognised via RFID), and then the fob sends the RF signal to the BeCM via the receiver etc etc to remove the "Disabled" condition (?).

My main question then is if the key is not first recognised via the RFID/coil system, will (just) pressing the fob button be the same ?
Or, and repeating this in another way, will the BeCM wake up (and also remove immobilsation) if the key is not actually in the ignition ?

In a word, yes. If passive immobilisation has kicked in (due to the delay between unlocking the car and starting the engine), then another press of the unlock button on the fob turns the immobilisation off. The key doesn't need to be anywhere near the ignition at all, it can be anywhere as long as it is in range so the receiver picks up the signal. My car, despite being a 98 but being built to a custom spec for plod, doesn't have the coil and until I turned off passive immobilisation, I got into the habit of pressing unlock before I put the key in the ignition just in case I'd left it too long before trying to start it. This is what has to be done on every early car without the coil, hence the message "Engine Immobilised, Press Remote or Enter Code".

I'll say it again, RFID is NOT used at all. It is the magnetic field generated by the coil. If you read what the document you quoted says, it is quite clear. The key is not recognised at all, as soon as you put the key in the ignition, the switch in the base of the lock (the same one that when it sticks will tell you the key is inserted when it isn't) tells the BeCM you have put the key in. That causes a pulse to be sent to the coil and the magnetic field generated by the coil causes the fob to transmit. This is the automated version of pressing the fob button, generating a coded radio signal that is received by the receiver, passed through to the BeCM and used to turn off the immobiliser as long as the fob and the BeCM are in sync.

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Being a bit pedantic there Richard (although technically it partly depends on the specific frequency of the pulses used of course....) but then clearly the P38 'super-secure' alarm system is actually much more stupid than I thought ! Makes sense that these keys are not really an 'extra layer of security' at all (as I also reasonably thought) but just a way to automatically 'press' the fob button again once the key is in the ignition. Wonder why it was removed on your car for 'plod' though ? Maybe the cars were a bit obvious if stolen ? Oh well....

Perhaps this aspect should all be called "inductive immobilsation" instead ? Still not ideal though ! I know: !IJACOCUTSAFP"
(It's just a couple of coils used to simulate pushing a fob button press) Never mind....

Yes, I have seen the relevant coil/inductance inside the fob of course - but had assumed that was also coded for particular keys/extra security too.' aka real RFID....
but then that would probably have cost them an extra 50p.... ?

Overall, and considering the mess LR are (still) in with their latest generation of "Keyless" alarms now perhaps i should not be so surprised it is not that sophisticated...

Finally in the interests of further pedanticism (!) i will send a note to the purveyors of that (potentially-misleading) link I posted in #26 too.....
Or else someone else may read it and get criticised on a Forum too !

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It's just a DC pulse, not RF at all. On my car I don't think the coil was removed rather it was never there in the first place as it appears to have been a base model when it came from the production line and went to LR Special Vehicles to be finished. It has the base model manual cloth seats (but with seat heaters), it has no cruise control, didn't have a trip computer (although it does now), it was supplied with no radio and the base spec speaker system (no mid range in the doors, only the 6.5 inch speaker), no wood on the door panels (although again I have swapped the door panels for ones with wood and mid range speakers), the 16x7 inch wheels on 235/70x16 tyres as fitted to a base model diesel and not the 8 inch wide ones on virtually every other car. But it then had the split climate control (rather than the manual system that a base model would have), the front fog lights, the headlamp wash/wipe and other 'useful' options added at Special Vehicles.

Anyway, we are deviating from the topic at hand, Frank's problem, so lets keep it back on track.

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No problem Ricard - and i just read and replied to your PM too ! ( ie. I was given some incorrect info. from an LR person who may have thought I was doing some industrial espionage or some such !)

(A few odd 'plod' modifcations there.... makes it more simple of course but at what aditional costs ?)

Yes, Back on track now; No further mentions of RFID either !

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Hi, I’ve tried the secondhand receiver bought from eBay and still no luck with it communicating with the bcem. Could I try the known good one or any other suggestions? Thanks, Frank.

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You are quite welcome to try my spare receiver although I suspect your fob isn't transmitting a signal even though the LED is lighting. The fact that it is held together with a tie wrap means someone has had a go at it before. I'm about to reply to your PM anyway.

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Frank you could also get a (basic) key fob tester on e-bay for about £20

('Basic' in that it only tells you if it is actually transmitting as the LED alone can't be trusted)

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What actually needs doing with a Nanocom if one is available? I'm in Huddersfield next Wednesday which isn't that far away?

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I'm confused too! Nanocom can enter the EKA but it isn't going to fix the fob.

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A Nanocom could be used to turn off the "passive imobilisation" so the BeCM has no expectations for the fob to (RF) transmit to it when the key is inserted.....?

(ie. Frank could have a duff fob or receiver -as Richard already indicated-... but with 'passive immobilisation' disabled he would then have to use the key to enter/start but not the whole EKA routine each time ? )

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Just been outside and tried it with mine to be absolutely sure my recollection was correct. My car and Frank's are both 98 models so should have identical firmware and react the same.

My car had been locked with the fob, so I unlocked it with the key.
Only the drivers door unlocked and when I tried to start it I got the Engine Immobilised, Press Remote or Enter Keycode message.
So I entered the EKA using the key in the door latch. All doors unlocked and I was able to start the car.
Switched it off and locked it with the key. Waited for the alarm LED to stop flashing quickly so it had set itself and unlocked it with the key, same thing, only the drivers door unlocked and when I tried to start it found that it was immobilised.
This time, instead of entering the EKA using the key in the door, I plugged the Nanocom in and entered it with that. That unlocked all the doors and allowed me to start the car.
Switched it off again and locked it with the key. Waited for the alarm to set itself and unlocked it with the key. This time, all doors unlocked and the immobiliser was turned off so I could start it without having to enter the EKA again either with the key or the Nanocom.

So that is what the Nano can do that the key can't. It will always remain in a state that it was in originally, locked with the fob but unlocked with the key so will need the EKA. Once the EKA has been entered directly from the Nanocom it resets everything so the next time it was locked with the key it remembers it was locked with the key so can be unlocked with the key and won't ask for the EKA.

Turning off Passive Immobilisation is a bonus so it won't need to be locked and unlocked with the key if it isn't started within 30 seconds of unlocking it.

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So, entering the EKA with the Nano is different to entering it with the key?
Was not expecting that.

But hey, P38 :)

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Yes it is, it resets everything so when you subsequently lock with the key it will allow you to unlock, and turn off the immobiliser, with the key.

A couple of further thoughts on Frank's problem. As pressing a button on the fob while the BeCM is asleep, doesn't wake it up means the receiver isn't passing any information to the BeCM. That could be because the fob isn't transmitting a signal or the receiver isn't receiving one. I've sent Frank a known good receiver to try but I would suspect, as the fob is held together with a tie wrap, that someone has already been in there to try to fix it and it isn't transmitting. I did wonder if the fob had been taken apart and the key blade fitted into a random fob from a different car. That wouldn't sync as the lockset bar code programmed into it would be for a different car and not match the lockset bar code programmed into the BeCM. But, if that was the case, it would still transmit a signal, which would still be received by the receiver so would still wake up the BeCM. You can wake up the BeCM with the fob from a completely different make of car or virtually any other 433 MHz low power device (which is what causes the battery going flat due to RF interference problem). So, it is still a toss up between a duff receiver or no transmission from the fob. If the former, trying my spare receiver should make it work, if the latter then the fob can be sent away and repaired.

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Well if it helps, Can see what can be arranged if Frank is available, seems fairly straightforward there.

Would I also be right in thinking you can test the door lock switches with Nanocom? Though probabbly little point as it sounds like we already know they are a problem anyway.

I've got the p38 systems license and the Thor license on mine, not the GEMS though. Which I don't think would matter for the bits above anyway.

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Ok so it is worth meeting up with the nano. First to enter the EKA and second to try and wake his BECM with a known- working fob.
Ok....

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If you've not got the GEMS licence it doesn't matter for this purpose. When you switch it on, you select P38, then GEMS so it is set to talk to a GEMS car. It won't connect to the engine but it will connect to all the other systems and it will only show systems that a GEMS will have. With ignition off, go to BeCM, Utilities, type the EKA into the box and hit the button. It will think about it for a couple of seconds then the other doors should unlock (unless both front doors are already unlocked), you'll get a message to say the code has been sent and it will be possible to start it. You can check the microswitches from the BeCM, Inputs page but from the fact that he can enter the EKA sometimes suggests that either the CDL switch or the keyswitch is intermittent so it may appear to be working when you check it but won't work all the time.