You can try that... but I believe they simply got lucky in the post mentioned... Grounding the various wires isn't 'bypassing the security system' but rather just mimicking the microswitches in the door latch.
I'll try to 'decode' that horrific paragraph - I know it's a copy/paste as whoever originally posted it obviously didn't understand paragraphs... (It's been going around awhile, and in fact had a guy on facebook message me with that exact posting the other week say I might be interested in it) are:
How to disarm the alarm...... I have discovered a way to override the range rover alarm system. I recently had the unpleasurable experience of the transmitter not responding while the vehicle was armed in the super locking mode. So the first thing I tried was the EKA procedure.....It did not work, in fact all it did was open the driver's door and trigger the alarm. All of the other doors including the rear hatch remained super locked. I attempted to start the vehicle and got a display on the dash that said "ENGINE IMMOBILIZED". I tried to resync the transmitter and that didn't do any good. After about an hour of trying to start the truck I got fed up and took of the driver's door panel to have a look at the wiring. I found a harness that comes from the actuator and plugs into the door control module; it has seven wires in it. Orange w/ black actuator motor (CDL Motor) Pink w/ black actuator motor (Motor Common) Blue w/ red alarm arm/ alarm disarm (Key Switch) Green w/ red alarm disarm (CDL Switch) Purple w/ white doors unlock (Door Ajar Switch - NOT DOORS UNLOCK) Orange w/ white (Superlock Motor) Black ground Grounding the blue/red wire momentarily arms the alarm and locks the doors.(with CDL open circuit (locked) triggering this to ground effectively is turning the key to 'lock') Grounding the blue/red wire a second time activates the super locking mode. (yes, this will do if done quickly enough - as with turning the key in the lock twice in quick succession) Grounding the purple/white wire while the alarm is armed will trigger (panic) the alarm. (because if the alarm is set and you open the door, it will set the alarm off) Grounding the blue/red wire when the alarm has been triggered will silence the horn and stop the parking lights from flashing. (this only tells it the door has been unlocked with something like the sill button - I wouldn't necessarily expect this to stop the alarm going off though) I discovered that if you ground the blue/red wire & the green/red wire at the same time it disarms the security system even if it is in super locking mode, the immobilizer is also disarmed and allows the vehicle to be started. (this is effectively just triggering the CDL to unlock, and the key switch at the same time - making the vehicle think that it's been unlocked with the key in the door. In theory if the EKA is disabled, then yes this would then let you start the vehicle) Grounding the green/red wire while the alarm is in a disarmed state locks the doors without arming the alarm. (yes - this is as if you've just locked the door with the sill lock button and not the key in the door and is normal) Grounding the purple/white wire while the alarm is in a disarmed state unlocks the doors. (this makes no sense as the Purple/White is the door ajar switch and has nothing to do with the central locking part) My actuator was unplugged when I tested my new findings
With all that aside....
In THEORY... If the EKA is disabled then you should be able to just unlock the vehicle and it should bypass all of the EKA malarky... or you might have to lock it first with the key, and unlock it again and it should unlock all the doors and let you resync the remote.
I would only recommend trying that on a decent charged battery, as low voltage to the BECM will cause all sorts of headaches no doubt.
Depending on the software version of the BECM, then (and I know this because I had one on my bench from Canada that powered up with the alarm going off, even after unlocking) even if the EKA is disabled, then doing the 'disarm' procedure in the BECM with Nanocom will still reset it. Obviously you need communication to the BECM for that though.. And the BECM software to be V36 or later.
This predicament is one of the reasons I don't encourage owners to disable the EKA when I reset lockouts etc - as you've found, there is no way if the EKA is disabled and it has a fit to get around it - well other then I've just mentioned above - but that requires nanocom at least!
I also don't believe that you will be able to enable the EKA with it in an alarmed/locked out state... Just like you can't disable the EKA or turn the passive immobiliser OFF when it's immobilised or expecting the EKA - because otherwise all someone would need to steal the vehicle is diagnostics to do that, and a manual key blade.
You might be able to 'write' the EKA setting back to 'Enabled' and it might say it's written successfully, but I believe if you exit out of the BECM and go back into it, it will have reverted to 'Disabled'
I would personally check the door latch microswitches whilst the battery is out an on charge - as if it's got a dodgy microswitch, then that could be causing it to not unlock properly with the key in the door and disarm like it should (in theory) with the EKA disabled. If this is the case then triggering the wires in the above post will mimic the key being turned and should get it unlocked... If that doesn't work, then it's possible the BECM has gone into lockout and will need resetting with something like my Faultmate to clear the lockouts from the CPU.
'06 4.2 Supercharged Black/Cream "Jess" -- Bought April 2021 (NZ)
'01 4.6 Vogue Black/Lightstone "Snog" -- Bought Jan 2012
'99 4.6 HSE Cobar Blue/Lightstone -- Sold March 2009
'95 4.6 HSE Epsom Green/Tan -- Traded June 2008