Continuity tests are necessary on the wires between the xyz switch and header joint C0724(which is embeded in that harness) the wire colours are the same from the switch to the header and from the header toward the BCU and EAT ECU
 
I've just had a mind flash.... put a 1A inline fuse on that new feed you made eventually if it doesnt blow measure voltage on it cos it might drop due to somne resistive short as if it drops below 10V the ECU will not recognise the outputs, also this can be the reason of missing feed from the BCU cos it has a protection in it and if it feels a short to ground it cuts the feed
 
Sorry guys just picked up messages just come in from a nightmare day in workshop on mowers lol I don't have any 1 ap fuses did not even no they went done that low
 
Hi all. i am yet another to have to this issue. I have done lots of reading on this, and theres loads of forums threads out there and mostly everyone says the same information.
I did all the recommended checks regarding battery voltage, strong connections on the leads, earth straps (i even added and additional engine to chassis earth lead to make sure) and then changed the XY switch for a brand new one. But nothing fixed it, until i went to my friendly local main dealer, where i got the key piece of information.
"9/10 its transmission wiring loom that has a broken wire, near where it fixes with the P clip".
Sure enough, on removing the loom i found a broken wiring on one of the T junctions. Only one wire was broken, and a few others had some slight chaffing. Soldered up the break and now even is back to normal.
very happy to finally have solved this issue
I will add some pics asap.
 
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also when reconnecting the loom, its best to remove the centre console veneer to be able to plug the connectors back in. (details on how to in the Haynes manual etc)
 

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Hi all. i am yet another to have to this issue. I have done lots of reading on this, and theres loads of forums threads out there and mostly everyone says the same information.
I did all the recommended checks regarding battery voltage, strong connections on the leads, earth straps (i even added and additional engine to chassis earth lead to make sure) and then changed the XY switch for a brand new one. But nothing fixed it, until i went to my friendly local main dealer, where i got the key piece of information.
"9/10 its transmission wiring loom that has a broken wire, near where it fixes with the P clip".
Sure enough, on removing the loom i found a broken wiring on one of the T junctions. Only one wire was broken, and a few others had some slight chaffing. Soldered up the break and now even is back to normal.
very happy to finally have solved this issue
I will add some pics asap.
Thanks for reply sorted mine out it had reverted itself back to manual mode in setting switched it back to auto in the diagnostic and all lights came back on dash and it's be sorted for the last few months if any one wants a brand new x y z switch I have a brand new Oem one I never used will sell it for £190 and thanks for info
 
Had this problem with mine....was told by a friend if the battery is giving out a good voltage, it could be the XYZ switch sticking. He told me to hold the auto gear stick button in and vigorously move it forwards and backwards a number of times. This sorted it and its been fine ever since :)
had this issue today and a quick search led me to this thread. saw this post and gave it a try - it worked!
sticky xyz switch. i suppose unless you use all the gears rather than just P, D and R, the switch could get gunked up. moral is, try the simple things first.
 
A friend had the M&S lights coming on intermittently? Checked battery voltage, but eventually found oil in the main ECU plugs. After cleaning and drying thoroughly no more troubles.
 
A friend had the M&S lights coming on intermittently? Checked battery voltage, but eventually found oil in the main ECU plugs. After cleaning and drying thoroughly no more troubles.
thats the next thing i will be checking. it doesn't seem to be running as smoothly as it should. nothing anyone else might notice but you know your own car. got a couple of unexpected days off so i'll be having a look.
 
If you're "going in" can I suggest you do something else? Check the MAP sensor on the inlet manifold. It's not at all unknown for these to be so caked up with black clag that they don't work correctly. Clean off with aerosol brake & clutch cleaner. Takes 2 to 3 mins but deffo helps with the running.
 
If you're "going in" can I suggest you do something else? Check the MAP sensor on the inlet manifold. It's not at all unknown for these to be so caked up with black clag that they don't work correctly. Clean off with aerosol brake & clutch cleaner. Takes 2 to 3 mins but deffo helps with the running.
i have actually done that fairly recently though i might give it another clean. i know my maf sensor is dead, (no signal on neilly's nanocom) but it was running ok on default. it just seems very slightly 'rougher' than it used to be with a kind of 'rumble' at around 2000rpm. my engine mounts have seen better days so that probably doesn't help.
 
You still have not fixed it? But I suppose at the time you had other things to sorry about....LOL.

Cheers
well... i did swap it for my old one which i cleaned up (very carefully!) but i dont know if that one was working as there was no noticeable difference. after having to splash out on a torque converter, i didnt have much left for a new maf sensor!
 
Hi guys my issue as been sorted it turned out to be the thing had reverted to a manual in diagnostics when I switched it back to auto everything came right .I bought an Oem xyz switch ready but have not used it still in box if any body wants one at a discounted price I’ll let it go for £280.00ono I think I paid about £350 with vat if any one is interested just message me on her
 

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