Thread: decoupling BCU from ECU... doable?

Hi. I've never tried so i'm not sure that the ECU can work without the security signal input delivered by the BCU unless you fit an emulator but you can try before you remove the engine from the D2 to use nanocom or similar and set the alarm to "not fitted" then unplug the BCU and see if the engine starts this way, it will not crank without the BCU so you have to splice into C0573-7 with and earthed wire(that's the starter relay coil's earth) and see then if it fires, if it cranks in vain you'll need something like this TD5 IMMOBILISER BYPASS on the security code wire. They say its for Td5 but the security signal from the BCU is not dedicated for the engine type so IMO you can make the V8 ECU as well to learn the security code with nanocom or find somebody who knows to disable the immobiliser with invasive method in the ECU cos it's possible. Good luck

The motronic ECU can be re programmed to run without an immo, but it's $$$.

You could possibly just fit the ECU from the V8 D2 along with the BCU, but without any of the other features of the BCU hooked up.

I think that would work.

OK so looks like it's the usual period-correct SNAFU where the engineers thought they were being smart but really prove to be ignorant of the possibility that someone may one day have to get the thing functioning without an interconnect.

Land Rover the best 4x4 f-ups by far.

Originally Posted by Mercguy

OK so looks like it's the usual period-correct SNAFU where the engineers thought they were being smart but really prove to be ignorant of the possibility that someone may one day have to get the thing functioning without an interconnect.

Land Rover the best 4x4 f-ups by far.

Everyone does the same thing, it's just for security/theft prevention.

Just like before radios were CANBUS or only designed to fit one particular vehicle, they had a security code.

You can get the immo turned off though if you really want, but I'd just fit the BCU with it, it would be negligible effort and expense.

Originally Posted by shack

Everyone does the same thing, it's just for security/theft prevention.

Just like before radios were CANBUS or only designed to fit one particular vehicle, they had a security code.

You can get the immo turned off though if you really want, but I'd just fit the BCU with it, it would be negligible effort and expense.

Yep and you're talking to a guy up to his neck in the upper eschelon of lockout-endusers - Mercedes.

It looks like the simplicity ended at D1. but that statement might find hostility from series owners.

And I thought the Prince of Darkness was enough. Looks like canbus intercept is a cheaper way to break it up.

Of course, this is a bmw-period and motronic was their thing, and all the lovely immob. function and integrated alarm etc was all a huge selling point for the euro brands back in the day... blaupunkt and Becker with their coded din mounted cassettes before that... then stupid MOST bus devices which instantly devalue and date a car if fitted.

Yep.... Those were the days!

You do realize of course that everything is tongue-in-cheek... I hate the primitive implementations as much as the next guy/girl, but it was useful - for a time. a very very protracted point in time....