02 TD5 90 - EML On & No Throttle + Zero Fault Codes

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
I just found it. Looks alright but im not going to attempt to remove it. Too much muck and sh!t in the way currently.

I did find a loose wire in the ECU box, coming from outside the box through the black plug socket. Blue/purple wire. Not plugged into anything...

So found **** all this evening, too dark to wash it when I get back from work so that will have to wait until Friday afternoon when I finish early. Going to ring Gigglepin tomorrow see if they have any ideas, seeing as they used to race TD5s they may know...
 
Last edited:
Don't forget that it needs to be in the fault condition while you are looking for the fault, if it is responding to the throttle correctly while you are playing with nanocom then you probably wont find anything amiss. If it is a wiring chafe it may be worth getting someone to repeatedly press the throttle while it is running so you can move looms around to see if you can induce the fault.
 
Spoke to Gigglepin, they said its most likely to be a chafed cable in the wiring harness getting wet and through the ECU out of whack. Which matches perfectly with what's happened to me. Apparently its most likely to be the part of the loom that runs across the top of the gearbox?
 
bankz5152 said:
Spoke to Gigglepin, they said its most likely to be a chafed cable in the wiring harness getting wet and through the ECU out of whack. Which matches perfectly with what's happened to me. Apparently its most likely to be the part of the loom that runs across the top of the gearbox?
Click to expand...
Sounds about right to me. If it's anything like mine I doubt if the Nanocom will 'see' anything, whether or not the Land Rover is showing the fault.
 
Right so today I chased the ECU loom round the car, could not find any damage or chaffing to speak of, well as much as my hands could touch anyway. All I did notice is that the ECU loom running above the gearbox is rather oily on the outside, cannot speak for the inside. Also there is one point on the black plug loom where it gets much thinner and looks as though it has been wrapped in leccy tape. Same place as where it is oily.

Just in case I am missing something and it is the throttle pot I took some live readings for your viewing pleasure below...





Small bit of good news however while chasing the ECU loom I found the wire that was causing the mis-lock on my alarm! It had come unplugged from the door switch and was shorting on the bulkhead.
 
@dannymcrtaylor Why would the ECU be dead? Landy is currently running fine, starts fine everytime, fuel pumps running, revs perfectly and drives. Idles fine as well. No oil or water in either plug.

Surely if the ECU was dead it wouldnt run at all or would be lumpy/misfire or at least show some kind of fault codes.
 
Last edited:
Yes, that's one plus side of these kinds of problems, it means that you go through the car systematically and find a number of little jobs to sort out.
You're not getting 'topside switch error' or 'topside switch failure' or anything like that? That's the sort of message that tells you it's an ECU fault.
Have you peeled back the corrugated plastic trunking that the wires go inside? Sounds a bit like you've just looked at the outside of it. Some say that the corrugations in the plastic help to wear through the wires inside.
 
: |

I have not no, I would have thought that if the plastic surround was in tact then the wiring inside would be alright! I guess not!

Car is still pretty mucky and starting to well, smell terrible. Ive got Friday off so ill be up early to jet wash it. Make it a tad easier to work on...

No fault codes what so ever bar the usual aircon fault. Topside switch failure/error is usually the crank sensor failure ay?
 
Care to elaborate a little? It seems unlikely the ECU is dead given my symptoms. I would expect if it is dead I would not be able to do a thing. Either way I will pop the lid off it tonight and check the inside for any water, oil, burns or general damage.

This sounds almost exactly whats happening to me....

http://forum.lro.com/viewtopic.php?f=18&t=80336

A lot of what I'm reading online suggest it could be the Crank Position Sensor, so I think am going to replace this. The genuine LR ones seem to be a tad 'rare' would the Bearmach/Intermotor ones be suitable? Though before I do I am going to search for breaks in the wiring more thoroughly. Apparently this issue can be cause buy water ingress into the back of the CPS plug.
 
Last edited:
Bit more research and all symptoms point to chaffed cable above the TX box or the throttle cable behind the dash.

So tonight I am going to remove the binnacle and try to chase the throttle wiring, there may well be damage here, if so it should be relatively easy to repair.

Also going to have another crack at the main loom over the TX/GB. I'll cut the cable ties off and attempt to clean up the area with some brake cleaner and the like, remove the tape I found and split the conduit see what I find.

Also reading this on Def2. It looks like these fellas made up their own wiring loom direct from the ECU to the pedal, looks like it could be a trouble free almost guaranteed potential solution.....

Luckily I don't really need my car until the New Year so I have some time to try and sort it, extra lucky that I have a heated garage!

Update -
While jet washing the bits i need to work on I sprayed the potential areas of trouble with the jet wash. Still started up fine and drove not far as I currently dont have a drivers seat... Just letting it drip dry a bit before getting it back in the garage.
 
Last edited:
Hi there. Yes, that discussion on Defender 2 net was the kind of thing I was thinking of, but couldn't lay hands on it. You might try as someone suggests on that thread and make yourself a temporary harness to go from the throttle potentiometer to the ECU - I see they list the colours and terminals that need connecting - and see if that helps. The wires are quite capable of wearing themselves away inside that corrugated tubing. The other thing that happens is that the conductors get brittle and sometimes break inside the insulation so that contact keeps getting made and broken with the vibration as you drive, hence the intermittent nature of the fault.
 
That would make sense. I dug into the loom a little more today from what i could see, the section above the GB is fine, managed to get a small look inside and the cables appear to be intact.

I have ordered some trailer cable off ebay, though short of removing the entire engine harness and checking bit by bit it would be a perminant solution.

Think i will replace that CPS at the same time for good measure. The i suppose its a waiting and hoping game....
 
I *may* be getting somewhere....

Traced the throttle loom behind the dash, stipped off the sheath and checked the cable. All good, no breaks. It then heads into a larger loom, into the engine bay and joins the main black plug loom. Still could not find any breaks but sprayed the area with WD40 anyway.

I then removed the plug from the throttle to check the connections more closely, all good again. I thought I would leave it unplugged and get some nanocom readings. Started up and there was no EML light, until I knocked the headlight switch. Suddenly after 15/20 seconds of running the EML came on, no other lights. Just as it did when I lost throttle.

Nanocom was reading the throttle as getting 5v, just stationary obviously.

So could it actually be the throttle pot? Despite where all the signs are pointing?
 
I was just reading over on Defender 2 that the 3 track pedal in the TD5, that the sum of the three voltage values should add up to 12v. If they do not it can result in loss of power, lumpy acceleration and limp mode. All of which I have experienced, just didnt realise until I read that. When adding up the voltages for my pedal I get between 8v and 9v (excluding the 5v input). Anyone confirm or expand on this?

Also thinking about the throttle pot wiring more, at the minute I am pretty low on cash so I want to avoid buying anything expensive that won't cure the issue 100%. If it is a wiring issue and I buy a new throttle pot I'm out £130. I also don't want to go chopping ECU cables for no reason. So could I put in a connector block? Like this which would let me have the ECU wired normally just with a connector added but I could then un-clip it and attach own loom (made with trailer cable) direct to the pedal? Anyone see any problems with doing this?

That way I can make the loom for £20, plug it in and see what happens. If it runs fine then the wiring is at fault and I'll leave it in place. If the fault happens again then the pedal is dead, I plug the ECU back to its main loom and replace the pedal.
 
Last edited:
More potentially headway here.....

I bought a voltmeter and check the continuity between the ECU black plug and the throttle pot multiplug. According to that all is connected as it should be, which would suggest no chaffing.

I did stumble upon a thread on here about crank speed which is apparently meant to be 300rpm or above, from the limited tests I performed with the Nanocom (kept freezing when I started up) my crank readings started at 140 - 200 and quickly jumped to 700. Which from what I have learnt would suggest a faulty Crank sensor. Which would makes sense to cause an intermittent fault. Driving along fine, hits water, causes a short throws up an EML fault, then dries out and its fine. Or hits a bump and dies again...
 
You must log in or register to reply here.

Similar threads

KISSMYAURA
TD5 No Throttle but engine running? Help!
Replies
16
Views
2K
KISSMYAURA
KISSMYAURA
Martin Radoczi
Disco 3 (LR3) Down on power, no fault codes. Where to look next?
Replies
14
Views
2K
gstuart
gstuart
S
3.6TDV8 RRS cranking but no start
Replies
1
Views
4K
ButcherBoy1968
B
G
TD5 Backfire / Cutting out / Driving me mad
Replies
5
Views
2K
sierrafery
sierrafery
Spot1
Disco 2 Auto box ? Electrical fault.
Replies
3
Views
665
sierrafery
sierrafery
Back
Top