Disco 1 Intermittent running fault

My lad has a 94 V8 D1 that decides now and again to go into a "limp mode", he is able to keep the engine running but has to pull over ASP. when he stops he locks and unlocks the vehicle thereby operating the immobiliser switch in the door and system. Then the D1 will run again no issues, normally all day. I am about to move the immobiliser switch and route it clear of the lock mechanism to ensure it isn't being operated while in motion. I don't know anything about this system, any suggestions of what to try please?
It doesn't have central locking working as when he got the vehicle all motors were goosed.
Is there a way of bypassing or deactivating the immobiliser system?

Ok, so deactivating as you are suggesting, the door micro-switch is at the rear of the door lock, check that the re-mobilising function is either with the switch ‘open or closed’ and make that one permanent. With any luck, u may find its as simple as disconnecting a wire or taping the switch ‘closed’.

Limp mode is associated with EFI ECU.

discool said:

Ok, so deactivating as you are suggesting, the door micro-switch is at the rear of the door lock, check that the re-mobilising function is either with the switch ‘open or closed’ and make that one permanent. With any luck, u may find its as simple as disconnecting a wire or taping the switch ‘closed’.

Limp mode is associated with EFI ECU.

Click to expand...

Many thanks for your reply, spent a couple of hours outside, learning the system. the micro switch and cam seem fine, not loose at all so traced the wiring to the central locking module. It appears that the CL module is therefore his immobiliser system too. opened up the control unit, simple clips and found a lot of corrosion inside and what appears to be burning on the board on 2 resistors. Having looked at a thread from 2009 our fault, could well be linked to this box, now sourcing a replacement. not a cheap option but swapping out the module might at least eliminate that area. all other diagnostics, HT/ fuel, earths and feeds have found no fault. A pity really, I hate intermittent faults.

Ok you have an understanding on what is involved.
You may know that 1994MY was disco a change over year when the 300series was introduced with the updated ‘passive’ immobiliser so a change from the previous active system.
1994 200series had a black security ECU with a single button fob for remote central locking, so a simple and straight forward swap, you should see a large standalone relay that looks after the central locking via a signal from the ECU.