On a 2005 the remote fob just does the central locking and alarm.
The immobiliser is a completely different system consisting of a chip in the key that communicates with a Sawdoc immobiliser ECU via the coil on the ignition barrel.
You can buy a replacement key with a chip already programmed from a LR main dealer parts department and it probably isn't as expensive as you think.
As far as I know, the key/chip will "just work" without needing the service department to get involved.
 
I think my key is a recut from a blank, but how it is in a LR holder intrigues me. I do have a chip in mine. 2005 Facelift.
 

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I think my key is a recut from a blank, but how it is in a LR holder intrigues me. I do have a chip in mine. 2005 Facelift.
Do you happen to have the dimensions for the chip? I doubt anything like that would fit my key, although they're branded as 'chippable'. I don't have it on me ATM so can't post a picture. I'm hoping my car is old enough to rely on the fob for the immo, as the chips seem impossible to get, but replacement fobs can still be bought.
 
Do you happen to have the dimensions for the chip? I doubt anything like that would fit my key, although they're branded as 'chippable'. I don't have it on me ATM so can't post a picture. I'm hoping my car is old enough to rely on the fob for the immo, as the chips seem impossible to get, but replacement fobs can still be bought.
I shall update you with the exact dimensions next week when I arrive home. 👍🏻
 
Do you happen to have the dimensions for the chip? I doubt anything like that would fit my key, although they're branded as 'chippable'. I don't have it on me ATM so can't post a picture. I'm hoping my car is old enough to rely on the fob for the immo, as the chips seem impossible to get, but replacement fobs can still be bought.
They used the 27VT as both alarm and immobiliser up until 1999.
From year 2000 they took the immo function out of the 27VT and moved it to a separate BMW based EWS3D and then in 2004 replace the EWS3D with their own SAWDOC system.
So, if your Freelander is 1997 to 1999 then you don't need to worry about the key chip, and it's all done with the alarm/central locking fob.
If it's year 2000 to 2006 then you have the chip in the key.
 
Bypassing the immobiliser is possible as I once saw a Freelander where it was done but I don't know how.

They used the 27VT as both alarm and immobiliser up until 1999.
From year 2000 they took the immo function out of the 27VT and moved it to a separate BMW based EWS3D and then in 2004 replace the EWS3D with their own SAWDOC system.
So, if your Freelander is 1997 to 1999 then you don't need to worry about the key chip, and it's all done with the alarm/central locking fob.
If it's year 2000 to 2006 then you have the chip in the key.

Does the immobiliser send CAN messages to the ECU or is it as simple as a GND or 12V signal?
 
on a 2000 on it uses a BMW rolling code system.
You can reflash the engine ECU to ignore the immo.
The immo also inhibits the starter motor so you would have to wire your own starter motor relay from the key to bypass it.
I don't remember what other things the immo interferes with, so you would have to look at wiring diagrams to figure that out.
I don't think it's on the CANbus
 
pre 2000 and post 2000 use completely different protocols from the alarm (pre 2000) / immo (post 2000) to the engine ECU
pre 2000 it's the old MG Rover EMS codes. This is a fixed code which is the same system as MG Rover 5AS and Pektron alarm systems.

pre 2000 engine ECUs can be put into a "learning" mode (pscan can do this) so that an ECU can learn or relearn the EMS code.

post 2000 it's BMW rolling code and only an unused factory state ECU can learn the rolling code and pscan is not capable of doing this. If you want to do an ECU swap on a post 2000 then the easiest thing to do is reflash to disable immo so that the engine ECU just ignores it
 
on a 2000 on it uses a BMW rolling code system.
You can reflash the engine ECU to ignore the immo.
The immo also inhibits the starter motor so you would have to wire your own starter motor relay from the key to bypass it.
I don't remember what other things the immo interferes with, so you would have to look at wiring diagrams to figure that out.
I don't think it's on the CANbus
It was a while ago but IIRC the car I looked at had a button to start it so the guy may have wired it into the starter relay.
I did a similar thing myself recently in my wifes Ford Kuga. It stopped recognising the clutch was pushed in even though I replaced the switch at the pedal so the Start button only put the ignition on.
I bought a push button with Start Engine on it and wired it into the starter relay. It works a treat and SWMBO doesn't care.
 
It was a while ago but IIRC the car I looked at had a button to start it so the guy may have wired it into the starter relay.
I did a similar thing myself recently in my wifes Ford Kuga. It stopped recognising the clutch was pushed in even though I replaced the switch at the pedal so the Start button only put the ignition on.
I bought a push button with Start Engine on it and wired it into the starter relay. It works a treat and SWMBO doesn't care.
I'm a bit confused here cos the immobilisation of the starter is an easy fix - just put a permanent earth on the relay.

However, its no good spinning the engine if there's no fuel being injected, that's the difficult bit to get around.
 

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