With Autologic he should succede if he knows his job...the fact that he worked for a maine dealer is not in his favour though;)
 
Bloke just rung up: are you all listening? ECU!!!
I was right! You lot were all WRONG!!!:D

Better still, he said they couldn't get any sense out of the old ECU; it wouldn't communicate with their diagnostics, so they swapped it over with a known good one, reset the codes and bingo! Fired up straightaway!

So if I'd have done as some here suggested and bought my own diagnostics box it would set me back 450 quid with nothing to show for it!:rolleyes:

Sometimes you just have to trust yourself and go with your instincts. :p
 
Depends on who you trust m8, i dont feel i was wrong, here's from page 9 in this thread http://www.landyzone.co.uk/lz/3513417-post88.html , then after you confirmed there's no feed to ECM it was logical to presume that it's the reason for the missing signal to the injectors too... if that missing feed to ECM was so intermittent it's possible that it occured to the guy who took it and then it's normal to not be comms with the ECM, the fact that you didnt find feed on those 3 pins at a moment then jiggled around and the feed came back has nothing to do with the ECM's internal fault, datalink failure is in 90% of cases missing feed issue not internal fault so if there were two unrelated faults, one intermittent with the ECM feed and one internal ECM fault from what you say at this moment only the ECM is ruled out and you can end up with non running engine any time due to missing feed
...So if I'd have done as some here suggested and bought my own diagnostics box it would set me back 450 quid with nothing to show for it!:rolleyes:
Sometimes you just have to trust yourself and go with your instincts.

^^^WRONG: you'd have got the same datalink failure and then confirming that the ECM has feed you'd have known it's ECM failure, bought a known good one cos the market is full and set it yourself with your own tester

the price would have been 300quid(inc VAT) for a hawkeye and around 100 for the ECM... and being covered for life with free diagnostics

let's hope everything will be OK from now one, i wish you good luck but IMO you'll end up paying more in time based on instinct than on a tester:rolleyes:
 
Ffs after all that time an effort by so many people and the blokes gleefully telling everyone they're wrong. :rolleyes:

Would you like to be reminded you burst in here not knowing what engine you had?

The whole point was you didn't want to pay transport to diags.

Plugging it in and finding there was no communication is what led to the solution is it not?

Get your own diags or put up with getting it to someone who has. You'll be struggling every time with a Td5 otherwise.
 
Sorry, it does appear I was gloating on re-reading it.
Seriously, I'd like to thank everyone who chipped in here regardless. Any of those suggestions could have been the money one. I just got lucky. :)
 
[...]
let's hope everything will be OK from now one, i wish you good luck but IMO you'll end up paying more in time based on instinct than on a tester:rolleyes:

Oh, I'd have bought a Hawkeye or that other one you use IF I felt I had a future with TD5s, but since they use these computer management systems, it ain't gonna happen. I plan to sell my TD5 later in the year and get something simpler and more true to the ethos. A Series 3 for example. I kind of miss having 3 different coloured gear levers as well. Classy!
 
that's your choice ... about the repair if you want to make sure about the fairness of the guy who fixed it check if the rocker cover was removed or not, cos if it wasnt and they couldnt communicate with the old ECM it means that the injector codes are not set in the replacement ECM(cos there are two ways of knowing them: reading the old ECM or reading the codes directly from the injector solenoids) in which case the engine will not run at full capacity... which mean you might loose money when you sell it;)
 
+1 with SF. The fact the feeds were missing and magically re-appeared when jiggling the wiring in the ecu area seems a more likely reason for the sudden failure. Perhaps there was a second fault in the ecu or perhaps the application of extraneous signals from external sources in an attempt to outwit the ecu caused a failure? We may never know. Still, glad it's sorted. Happy motoring.
 
I reckon he buggered it by messing about with resistors and stuff :p but then again I would say that seeing how massively unhelpful I've been in the rest of this thread.
 
+1 with SF. The fact the feeds were missing and magically re-appeared when jiggling the wiring in the ecu area seems a more likely reason for the sudden failure. Perhaps there was a second fault in the ecu or perhaps the application of extraneous signals from external sources in an attempt to outwit the ecu caused a failure? We may never know. Still, glad it's sorted. Happy motoring.
I'm glad you got it sorted but I'm with Derek here. Wiggling the wiring restored voltage which tells me 100% it was a wiring issue that caused the initial problem. Subsequent investigations likely fried the ECU but I guess we'll never know. I have dunked ECUs in pond water while laning, dropped them taking them out, and they worked just fine after drying them out. Every time I have had need to trace a so called ECU fault (not only on LRs) the cause was wiring related. Only once did I find a genuine fried ECU but the doughnut who's motor it was had connected the battery reversed and then tried to start the engine. Chances are he would have got away with it if he had not switched the ignition on.

I personally know of three DIY "experts" who after spending 10 mins on google and youtube fried their expensive ECUs by poking around applying battery voltage to various places in the hope of finding their electrical gremlins. Some of the crap on youtube is guaranteed to fry delicate electronics. If you know what you are doing it can be a valid diagnostic technique but if you make just one mistake and apply voltage to the wrong pin or accidentally short an ECU voltage switched circuit or reference feed to ground then bye bye ECU.

I would not be surprised if the initial intermittent wiring fault comes back at some time as you never actually found and fixed the wiring problem. The TD5 is a reliable beast with minimal electronics compared to modern cars and with a little knowledge and minimal diagnostics will serve you well for many years.
 
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+1 with Shifty.

IMO, ECU,s dont just fail.

Have a browse on Disco3 site, some epic "faults" all caused by "mechanical" electrical problems, crushed wires, dirty connectors etc.

Ive been putting a paper together, for a work related project, on best practice for maintenance of electrical equipment, lots of really meaty stuff from US Navy/Air Force on how to fault find problems, rectify and prevent electrical problems. The US navy ones are good, try keeping a modern jet air worthy, when daily its getting drenched in salt water!

It really isnt rocket science and it doesnt cost a fortune. Believe it or not, cotton buds and tooth brushes feature a lot in their official guide notes!

Ill post up some links if anyones interested.

I suppose this thread did remind everyone what a bunch of muppets LR dealers are though, so I guess something good came of it!

Mark
 
I personally know of three DIY "experts" who after spending 10 mins on google and youtube fried their expensive ECUs by poking around applying battery voltage to various places in the hope of finding their electrical gremlins. Some of the crap on youtube is guaranteed to fry delicate electronics. If you know what you are doing it can be a valid diagnostic technique but if you make just one mistake and apply voltage to the wrong pin or accidentally short an ECU voltage switched circuit or reference feed to ground then bye bye ECU.

Oh, I fully agree; not a suitable environment for ****ers. But do please remember I do this kind of thing for a living. Almost all the tests I carried out were very light-touch and couldn't possibly have damaged the ECU. The loading an oscilloscope places on a circuit is feather-light (30pF || 1Mohm) and the crank sensor emulation procedure was precisely the voltage level the ECU would be expecting and I delivered it via a 600ohm source impedance, so no danger of burning anything out there either. And yes, I took the customary anti-static precautions. Do give me SOME credit FFS!!!;)
If I can persuade the bloke to return me the old ECU I'll open it up and check those caps you or Shifty mentioned, btw. If it's one of those that's gone I'm sure to have an equivalent 'in stock' so can fix it; get some money back by re-selling it on fleabay.:)
 
IMO, as long as you pay for the replacement ECM it's normal to get the old one back without any persuation otherwise it's suspect, me i don't think you ruined the ECU with impulses cos as long as you don't exceed 12V the ECM has it's own protection, it's ''prepared'' for ''short circuit to vehicle supply'' on all sensors as it appears in the sensor's signal failure possibilities... i have those suspicions which i've already exposed in my previous post, i'm curious about how they programmed the injectors in the replacement ECM if they didnt take off the rocker cover as long as they couldn't comunicate with the old ECM to read them from it's memory
 
Of course they do! It might not happen every day but none of these intricate components, especially in an automotive environment, has an indefinite life-span.:rolleyes:
i agree... but in 99% of cases you can comunicate with them and get those common fault codes which i kept repeating... datalink failure is a sign of missing feed not internal fault
 
i agree... but in 99% of cases you can comunicate with them and get those common fault codes which i kept repeating... datalink failure is a sign of missing feed not internal fault

The nonsense codes were probably due to the various tests I carried out. I'm sure the unit was 'thinking' WTF????!! while I carried them out; it would be more than its brain could handle so it's hardly surprising it's stored stuff that makes no sense.
 
Of course they do! It might not happen every day but none of these intricate components, especially in an automotive environment, has an indefinite life-span.:rolleyes:

Ok got me there! I should have added...its usually something external! I too mess around with fairly intricate electronics, a lot of which has been ticking on nicely for over 20 years, over 30 in some cases.

But, as you have probably seen, random failures seem to occur more often since the introduction of RoHS, depending on the quality of the manufacturer!

Mark
 
Also, ECUs can have intermittent faults too, as well as wiring looms and connector blocks. Mine had something like that in the early part of this year. On passing the car over to a garage, they were able to swap it with one in a car with a good wiring loom and confirm that it allowed the engine to run occasionally, but not for very long, and gave 'topside switch error' on other occasions. It wasn't straightforward, because mine had wiring loom problems and a malfunctioning alarm immobiliser unit too. It's often hard to tell what's caused what. A faulty wiring loom may overload the ECU, or things can develop faults simultaneously by coincidence. Life's rich tapestry.
 

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