M and s lights

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Yes, the adaptive values can be reset with Autologic.The engine ecu will then be able to get the oxygen sensors cycling for proper closed loop operation.As I said they are very fussy,so it should be OK after that.There is always a chance that there is a physical problem with the Can pair but its very unlikely - in diagnostics you can NEVER say never... But being that the fault only flags when you get to 3000rpm it follows that its most likely a lack of message being put out on the can - bearing in mind the can is active as soon as the ecu's boot up and are pretty much constantly sending messages back and forth.
The other point I would make is that its all very well quoting P codes and their meaning,but in the diagnostic world they are only used as a guide - the ecu's can only report something they don't like using the nearest code they see as being correct.Often its miles from the actual cause and can only be taken with a pinch of salt.The main thing is that if it returns after noting and clearing is that whatever the fault is - it is clearly a current,not historic fault.Then you have to think a little further out of the loop as to the ACTUAL cause,rather than just relying on the written list.
 
The other point I would make is that its all very well quoting P codes and their meaning,but in the diagnostic world they are only used as a guide - the ecu's can only report something they don't like using the nearest code they see as being correct.
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i dont want to contradict just to share what i know, i've studied deeply the diagnostic systems...at least those for aircrafts:), i hope i can explain well in english: what i know is that a dedicated diagnostic tool must interact with the ECU's diagnostic protocol and has the specific codes stored in memory... the ECU-s software has some well delimited inputs stored which would trigger a fault code... each code has it's specific alocated "xxx" baud signal which is filtered and sent out by the ECU, when the tester recognise the signal it displays the correspondent code from memory... a Land Rover specific tool must display the codes as the builder conceived them and can't display other codes as it doesnt have to have them in memory...so IMO by exploring the EAT ECU or any other ECU with the proper software the displayed code must be one of those from the list in the book...as long as it's a dedicated tool for that job ...i hope it makes sense cos that's the best i can:eek:

in the end these are just some simple electronic EEPROM/microprocessor kind of things not some artifficial intelligence :)
 
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sierrafery said:
i dont want to contradict just to share what i know, i've studied deeply the diagnostic systems...at least those for aircrafts:), i hope i can explain well in english: what i know is that a dedicated diagnostic tool must interact with the ECU's diagnostic protocol and has the specific codes stored in memory... the ECU-s software has some well delimited inputs stored which would trigger a fault code... each code has it's specific alocated "xxx" baud signal which is filtered and sent out by the ECU, when the tester recognise the signal it displays the correspondent code from memory... a Land Rover specific tool must display the codes as the builder conceived them and can't display other codes as it doesnt have to have them in memory...so IMO by exploring the EAT ECU or any other ECU with the proper software the displayed code must be one of those from the list in the book...as long as it's a dedicated tool for that job ...i hope it makes sense cos that's the best i can:eek:

in the end these are just some simple electronic EEPROM/microprocessor kind of things not some artifficial intelligence :)
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Exactly,well explained. But in the real world on a daily basis people carrying out diagnostic jobs see fault codes that they know are misleading and with experience get to know what that particular code they see ACTUALLY means.The best example of this I can give relates to air suspension on P38 Range Rovers.The code "Pressure signal constantly high" rarely if ever means the reservoir pressure is constantly high,or even that the pressure switch is stuck in that state. What it actually means is that the valve driver switch pack on the eas valve block is failing.I was told this by LR tech support many years ago after much testing and checking on several cars.They couldn't tell my why it caused the fault to be logged,and I never bothered to work out why - I was just glad of a fix which worked.(There is no electrical connection between the pressure switch and drive pack,so no simple explanation)
My only guess is that the EAS ecu sees a set of data which it does not like,but it can only work with the software it was given.It cannot think beyond what it can see or reason why its seeing what it sees.Here is where we as diagnostic techs have to look further,I have been doing it for to long to be interested enough to try to work it out,now its just a job,get it fixed,get it out,next job in.
 
So I decide to invest in nanocom evolution.

There is only one gearbox fault

P0722 stall speed monitoring

Turns out the 'specialist' I went to with his expensive equipment must have been an absolute ****** because according to rave this means torque converter slipping :/

I reset all the adaptive values....same fault and no others

Do you think I should replace the torque converter then?

Cheers
 
run a live stall test on it to confirm and if the result will be the same IMO you need a new/rebuilt TC... see RAVE - auto. box - adjustments
 
I was thinking that. So If I do a stall test that would point me in the direction of mechanical or electrical??
 
Stall test completed 2200rpm no problem. So this means the torque converter is fine yes??

So where to go next???

Cheers
 
it seems that there's no mechanical problem then... clear the fault and go for a ride...if some different fault will come back it means that it's that strange CAN communication issue induced by the engine management(as eightinavee explained) and being a V8 my knowledge is over...or it could be an EAT ECU missbehaviour too...i dont envy you with that strange issue
 
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I have done that a few times. Exact same fault and the only fault religiously the same behaviour with the changing up at 3k rpm etc. There are no engine faults or anything :/
 
put the nanocom on instrument mode and watch the live data while the symptom occures...eventually save the live data and analise the sheet after that, maybe something will look suspect at that certain moment
 
Thanks mate ill give that a go.

At the minute im swaying towards it being the speed sensor...purely because the fault clears and stays cleared even when maneuvering around and only flags back up after a normal drive and with it being the exact same fault and symptoms.

So I think I may try and source one :/
 
Ok so ive run the live nanocom and im getting 0 on turbine speed rpm and 0 on output speed rpm.

Any ideas??

Cheers
 
at least you've got something to think about now and you can try to figure it out or hope that eightinavee or some other knowleadgeable guy who knows about V8 management will reply...cos unfortunately my knowledge ends here... when it comes about engine management i know only about Td5, but what i can presume is that if there's an ECM output issue it will affect the EAT ECU too through CAN signals ...good luck:eek:
 
I believe I may well have found the solution to my problem. That being the output shaft speed sensor in the gearbox. I have measured its resistance and its 300ohm I believe this value should be around 900 to 1200 ohm.

Im going to try and source one and fit. Ill let you know how I get on.

Thanks very much for all your help and advice.

It seems the land rover specialist i went to was not such a specialist at all. Lol ******
 
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