Henry.adams

Active Member
D2 been sitting for 2 years. When I first went to start the alternator started smoking so I swapped that out then no crank and electrical problems like no locks or indicators so I’ve checked the ecu on another truck And that’s all good replace the internal fuse box and bcu from a working truck with matching codes and still can’t connect to the ecu with a nanocom I’m really stuck at what to try next anyone got any ideas
 
D2 been sitting for 2 years. When I first went to start the alternator started smoking so I swapped that out then no crank and electrical problems like no locks or indicators so I’ve checked the ecu on another truck And that’s all good replace the internal fuse box and bcu from a working truck with matching codes and still can’t connect to the ecu with a nanocom I’m really stuck at what to try next anyone got any ideas
All the ECUs share the same communication line on the diagnostic socket, so any faulty ECU could stop communication with the engine ECM, even though the ECM itself may be perfectly OK. Can you communicate with the BCU for example or with nothing?

Is the ECM and BCU getting power?
 
All the ECUs share the same communication line on the diagnostic socket, so any faulty ECU could stop communication with the engine ECM, even though the ECM itself may be perfectly OK. Can you communicate with the BCU for example or with nothing?

Is the ECM and BCU getting power?
I believe I’ve now fixed that problem by replacing the engine bay fuse box. Now I need to get the immobiliser off and I don’t have the code is there any way to do that ?
 
I believe I’ve now fixed that problem by replacing the engine bay fuse box. Now I need to get the immobiliser off and I don’t have the code is there any way to do that ?
I don’t know of any way of getting the immobiliser off without the EKA code or the correct remote fob, sorry.
 
I have what should be the correct key should that not remove the immobiliser?
Hi, the correct fob should remobilise but not just like that, you have to make the ECM to learn the security code if the BCU or ECM was changed(it's in utility) but you can't do that as long as the ECM doesnt communicate with nanocom. Unless you replaced both the BCU and the ECM which were already paired though at what you described in your first post about locks and indicators i'd change the interior fusebox first

security-ode-ECM.jpg
 
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Do you mean just the key, or the remote fob? I think the remote fob is needed to re-mobilise but @sierrafery is the real expert here.
I’ve got the factory key with remote central
Hi, the correct fob should remobilise but not just like that, you have to make the ECM to learn the security code if the BCU or ECM was changed(it's in utility) but you can't do that as long as the ECM doesnt communicate with nanocom. Unless you replaced both the BCU and the ECM which were already paired though at what you described in your first post about locks and indicators i'd change the interior fusebox first

security-ode-ECM.jpg
ive got the electrical problems fixed by replacing engine bay fuse box so should I swap the original bcu and internal fuse box back in then will the key fob take the immobiliser off ??
 
I’ve got the factory key with remote central

ive got the electrical problems fixed by replacing engine bay fuse box so should I swap the original bcu and internal fuse box back in then will the key fob take the immobiliser off ??
What have to got to lose by trying?
Sounds good to me but then I have Van Goghs ear for electrickery!:D
 
ive got the electrical problems fixed by replacing engine bay fuse box so should I swap the original bcu and internal fuse box back in then will the key fob take the immobiliser off ??
First of all do you see the alarm's red LED when you turn ignition on? if that's the case then it's immobilised and as long as you can't communicate with the ECM the only chance you have is to use the original BCU which once worked and to be sure it reacts to the fob's unlock command though the lack of comms with nanocom points to another issue too
 
First of all do you see the alarm's red LED when you turn ignition on? if that's the case then it's immobilised and as long as you can't communicate with the ECM the only chance you have is to use the original BCU which once worked and to be sure it reacts to the fob's unlock command though the lack of comms with nanocom points to another issue too
It’s definitely immobilised got hazards and horn going off should I be able to communicate with the ecu while it’s immobilised then?? Because it’s like the ecu is blocking me from communicating milage on dash drops to 0 when I try to connect with nanocom then returns to normal when I stop trying to connect
I was connected with nanocom Briefly then I got locked out
 
Problem solved

Engine bay fuse box and bcu where both faulty

used the key from the car I removed the bcu from to de immobilise and then I all worked fine
 
So do you say that the engine starts and runs each time without making the ECM to learn the security code ? :eek:
I did have to learn the security code but the car wasn’t allowed me to do it for some reason so I dig out the old key fob from the disco I removed the bcu from pressed the unlock button which then allowed me to learn the security code with the nanocom Now it starts no problem
 
So basically I used the key from another disco that was still paired to the bcu to unlock the immobiliser which then allowed me to sync the ecu to the bcu.
 
Yes cos while the BCU is immobilised you can't communicate with any ECU, it's clear now, i'm glad it's sorted
 
Hi guys I have the crossed b on the dash on my disco td5 changed fuse box and bcu from a running car. And left ignition on to try and sync them but even after about 20 mins on nothing has changed. Any help would be great. Cheers
 
Hi guys I have the crossed b on the dash on my disco td5 changed fuse box and bcu from a running car. And left ignition on to try and sync them but even after about 20 mins on nothing has changed. Any help would be great. Cheers[/QUOTE
Have you changed both fuse boxes ?
 

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