Defender TD5 wont start

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So if I could get hold of a Discovery ecu would I have to set anything with a Nanocom just to see if it would power up (not even needed to start) ?
 
When we put a Disco TD5 ECU on my Defender, it started first time with out doing anything but would'nt rev. Had to change summet with Nanocom so that ECU would talk to accelerator.
 
Long shot but we had a works Td5 that started doing the following:

Engine would crank over but not fire, temp gauge almost into the red (when engine was definitely cold).

Turned out the be one of the yellow relays under the drivers seat. When ever it happened we used to give the relays a wiggle (technical term) and the engine would fire! Sometimes just slamming the drivers door hard would short it!

Might be worth a try?
 
Just seen your post :(

Another day another update !

ECU has good earths at the 4 wires on the black plug

It also has good wires to the relays under the seat.

What it does not have is 12v !. It should have it at pins 3, 22, 27 and 33. We only have it at 33 so spent the rest of the day following the brown with ornage trace wires aqround the whole car (dash, engine bay etc). Wherever we find the wire when its supplied with 12v the ecu powers up and we get a running engine !

Once the engine is running the temp gauge behaves normally it seems - until you use the sidelights, headlights, indicators and handbrake !.

I think this means one of a few things - I have either a bad earth, a broken 12v supply or a 12v supply thats shorting to earth before it gets to the ECU ?! Input would be appreciated with those ideas as im not electrically minded !
 
Just seen your post :(

Another day another update !

ECU has good earths at the 4 wires on the black plug

It also has good wires to the relays under the seat.

What it does not have is 12v !. It should have it at pins 3, 22, 27 and 33. We only have it at 33 so spent the rest of the day following the brown with ornage trace wires aqround the whole car (dash, engine bay etc). Wherever we find the wire when its supplied with 12v the ecu powers up and we get a running engine !

Once the engine is running the temp gauge behaves normally it seems - until you use the sidelights, headlights, indicators and handbrake !.

I think this means one of a few things - I have either a bad earth, a broken 12v supply or a 12v supply thats shorting to earth before it gets to the ECU ?! Input would be appreciated with those ideas as im not electrically minded !

Are you saying that you now have it running?
 
Just seen your post :(

Another day another update !

ECU has good earths at the 4 wires on the black plug

It also has good wires to the relays under the seat.

What it does not have is 12v !. It should have it at pins 3, 22, 27 and 33. We only have it at 33 so spent the rest of the day following the brown with ornage trace wires aqround the whole car (dash, engine bay etc). Wherever we find the wire when its supplied with 12v the ecu powers up and we get a running engine !

Once the engine is running the temp gauge behaves normally it seems - until you use the sidelights, headlights, indicators and handbrake !.

I think this means one of a few things - I have either a bad earth, a broken 12v supply or a 12v supply thats shorting to earth before it gets to the ECU ?! Input would be appreciated with those ideas as im not electrically minded !

id change main earth leads or at least help then with a jump lead between transmisson/body and battery
 
Use maintenance spray and not wd40 on terminals of fuse box, look for high resistance in ign switch/relays etc.

You want to clean all earths as you have major earthing issues, glad rattys imobiliser check and my words of advice are helpful. If you have engine starting thats progress
 
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I can make it run with a direct battery supply to the brown/orange wires that supply the ecu, maf, egr, ac and a couple of other things but it cant stay that way as it must be switched by ignition normally.

Its deffo not immobiliser - Ratty confirmed that with Nanocom :)

It looks like those supply wires are switched by either main relay, glow relay or fuel pump relay and I know ive got power to the fuse box so its somewhere inbetween I think.
 
I can make it run with a direct battery supply to the brown/orange wires that supply the ecu, maf, egr, ac and a couple of other things but it cant stay that way as it must be switched by ignition normally.

Its deffo not immobiliser - Ratty confirmed that with Nanocom :)

It looks like those supply wires are switched by either main relay, glow relay or fuel pump relay and I know ive got power to the fuse box so its somewhere inbetween I think.

Yeah Nanocom said mine was working fine too :rolleyes: and it was. BUT thats the point, without power to switch it off it STAYS immobilised ;)
 
Sorry to hijack this thread but I need similar help on this and it seems all the td5 electro wizards are here ;)
Friend has got a td5 that we are rebuilding. It's completely stripped down at the min so we took the fuel pump out of the tank cleaned it up and put it back in, changed fuel filter all pipes and wires on the same as we labeled everything.
Run the bleed cycle and fires up, soon as the engine runs the ECU cuts the fuel pump off or similar, then we cannot start the engine again until we've ran another bleed cycle.
What would be telling the ECU to cut the fuel pump or switching the engine off as soon as the engine fires up??
If you try start it with out running a new fuel pump cycle it won't run and the battery will just go flat.
Any ideas??
We've left it for a few months now just given up on it for a while lol..

It's a 52 plate if that helps..
 
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Edited lol. Eka is for the immobiliser thanks ;) So you can find the eka code by plugging a diagnostic tool in and how do you enter it lol? We're both useless when it comes to td5 elecys..

Could the ECU of imbolilised itself when we took the fuel pump out by any chance?
 
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Edited lol. Eka is for the immobiliser? How does one go about finding the code and entering it lol? We're both useless when it comes to td5 elecys..

Could the ECU of imbolilised itself when we took the fuel pump out by any chance?

OMG :eek:

Main dealer ought to be able to supply EKA code for the original vehicle whatever that was in this case :confused:

It's then a fairly simple combination of key turning opening doors and bonnet dependant on the EKA number supplied.

In this instance I think you will need the EKA code for the Disco's ECU BUT I'm not sure how well that'll work if it's the original immobiliser.

Maybe that's the problem the ECU doesn't recognise the immobilser and visa versa have to admit thats a bit beyond my knowledge :eek:
 
Haha ok thanks for that.
At the min it's down to the bare chassis with just the bulkhead&tub in place so will struggle reseting it by opening doors& bonnets and no keys :rolleyes:
Will get a land rover garage mate to have a good look at it with a laptop..
 
I think ive got the problem sorted but need to 100% confirm at the weeend before getting too excited - if I have ill put all the info here for future readers :)
 
The wire between the main relay and the inertia switch was the dodgy one (think it is white with a green trace).

The plastic had a slight slit in it and there were only two strands left - strange as it had nothing to rub on and was wrapped in conduit sleeving !

Seemed to test ok with a multimeter but could not pass load so stripped back and twisted together and now works :D

Spent the last few days refitting all the dash, boot floor and wiring plugs etc that we had removed to test.

Now just awaiting an injector loom to arrive along with a replacement relay and base for the glow plug relay.

Im going to seal the ECU casing back up but need to find two screwes for it to replace the missing ones but they are proving hard to find :(

Massise thanks to everyone that gave advice, came out to look and offered to help - its all been very much appreciated :)
 
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