P38 2.5(98) lock out

Hello everyone long time since commenting on this page or asked for help... I have a 98 2.5 p38 had it now for 10 or more years but its been parked up and stored for a long time now and its about time i pulled my finger out and got it back on the road. First problem my memory lol its been that long that i can't remember the tricks of running the p38, ive had many problems and where i could have fixed myself in the past i have . Second problem and this is what's stopping me sorting the rest out, it has gone in to lock down i have the code for the door lock but not working (no lights flash on the dash when in puting Code)tryed disconnecting rf box in boot as have had to in past and no help. I've sprayed the door lock and moved the wires about and it did nothing.... Please help can't think what to try next or how to find what's wrong . I've heard you can get it plugged in so you can bypass the engine Immobilise (turned it off). I have 3 keys( new batteries) none unlock car by button ( they use to ) .
Im based in Colchester essex if anyone can help it would be great

How long since it's been run?
Is it likely that with the lack of use & the cold weather that the battery is now completely flat?

Battery is not flat as charged it up but will buy a new one just to rule it out. Car been sat about 5 years.

If the battery has sat for 5 years unmaintained then it's likely goosed. If you turn the headlights on, what voltage do you get at the battery?
Key will probably need resyncing with the receiver plugged back in.. press and hold lock, put key in the door and turn to lock, wait for the fob to stop flashing them repeat with unlock. Sometimes needs to be done a few times

Here`s a test sheet to check if your lock is working properly

Start.....key turned to locked & back to vertical four times. <<Tells the BecM you are now

going to enter the EKA Code>

Then <1st digit> entered in the unlocked (clockwise) direction and back to vertical for

each time.

Then <2nd> digit entered in the locked (anti-clockwise) direction and back to

vertical for each time.

Then <3rd> digit entered in the unlocked (clockwise) direction and back to vertical for

each time.

Then <4th> digit entered in the locked (anti-clockwise) direction and back to vertical for

each time.

Finally, Turn once to unlocked and all the doors should unlock and the car "should" be

re-mobilised.

It is very important to make sure you deliberately and carefully execute each keyturn

AND back to vertical (and no further).

The doorlock contacts do go dodgy with age & use.

The flashing of the side-repeaters or the dashboard lamp (depending on how the system

was set up) are your only indications that your entries are being seen.

If they are not consistently being seen then you will need a Nanocom to re-mobilise the

engine.

If the switches are inoperative then EKA entry may be simulated by shorting the wires at the plug(s)

if you have access to the inside of the door on the driver’s side with the door-card removed.

A short between the Black Wire and the White wire simulates an “Anticlockwise” or “Lock” action of

the key.

A short between the Black wire and the RED wire simulates a “Clockwise” or “Unlock” action of the

key.

This may (at the very least) enable the EKA code to be entered and normal key-fob locking/unlocking

and engine starting to resume.
Hope this is of use

I will get a new battery sorted and then give everything a try and hope it works. Thanks for all the info.