P38A P38 gearbox issue help

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Beastly_p38

Beastly_p38

Member
Posts
26
Location
Midlands
hi,

Firstly hello I’m Dom 31 years old from the midlands I own a 2.5 turbo diesel p38 and this is my story thus far.

I bought her about 8 months ago in great condition just needed touching up in places. Mot came round and it weren’t good at all, so I started replacing things, break calipers break discs break pads all round then the CV joints then found the prop shaft was loose so replaced that the drag links and trac rods then D bushes then the arm bushes had completely failed so I replaced them all with polly bushes drop links she had a full service all fluids replaced and about £1200 later she was sailing down the highway like a new rangie.
Anyway 2 days after all this work was carried out I started the car like normal, it was -5 our so gave it 5 mins to warm up then tried to select reverse and it seemed reluctant so let her warm for longer and then she slotted right in, after backing out the drive I tried to select any other position in the auto box and it would go threw the gears fine but the little red LED would remain in the R position, so I turned engine off looked at the atf and saw that was perfect as I New it should be, anyways I gets back in her and tried to start her back up and she says she’s still in reverse even tho it’s in park and I can select any other gear.
I’m thinking this is the linkage underneath as I checked the gear gator and saw that was doing its job, I tried searching on here as a long time admirer of the site but that turned up trumps. So I took the plunge and signed up this is my problem?? Can anybody help me? Has anyone had this problem? Cheers Dom
 
I would be checking the cable to the XYZ switch on the side of the box or indeed the XYZ switch itself.

The XYZ switch is fitted to the side of the box and informs the gearbox ECU what position the drive select lever is in....

Remember ATF should be checked with the engine running, in N and cold.
 
Remind me what XYZ means again? Where are boththese located? The ones by the box? The other is under bonnet or seat?

Thanks for replying
 
As I said in my post above, the XYZ switch (yes that is what it is known as) is mounted on the side of the gearbox and is moved by the cable linked to the drive select lever (gear selector in the car!).

It tells the gearbox ECU what position the gear selector is in and what to do to manage the gearbox and changes.

If the cable has snapped or is out of adjustment could cause your issue, as can a broekn XYZ switch....check both and also the wiring to and from the gearbox ECU to the XYZ switch.
 
Cheers guys I’m sure it’s not a wiring problem, so the switch sounds plausible, iv decided to book it into a garage this morning as it’s -6 here and I can’t be bothered to work in that so I will see what they say
Cheers guys
 
Right guys quick update, xyz switch is doing its job linkage is working as it should everything my bing as it should but the car still thinks it’s in reverse so all out of ideas, iv took battery off tested that and it was a little low so put it on charge just to see if that could cause it to do such a thing. Still scratching my head tho
 
Odd...it could be the gearbox ECU....

If it thinks it is in reverse, it can only be the XYZ switch which tells the ECU which position the drive selector is in or the ECU isn't interpreting the information from the switch correctly.....
 
Well that’s it because as I was u set her earlier everything is plugged in and moving as and when it should I checked ecu under passenger seat and all seemed fine this has really baffled me
 
Beastly_p38 said:
Well that’s it because as I was u set her earlier everything is plugged in and moving as and when it should I checked ecu under passenger seat and all seemed fine this has really baffled me
Click to expand...
Can you re-phrase the above - it doesn't seem to make sense?

Visably looking at an ECU won't tell you anything....unless you are an electronic genius with xray vision!

Whilst the cable maybe adjusted correctly and attached firmly to the XYZ switch, it doesn't mean the switch outputs are working or correct or indeed that the ECU is interpreting those correctly.

The RAVE manuals give a matrix to how the various contacts on the XYZ switch should read at varying drive selector positions, has this been checked and all switch contacts are OK as per the matrix? Have you had it on diagnostics to see if the ECU is reading the XYZ switch positions correctly?
 
Ha ha awfully sorry about that, I was rushing and iPhone predictive text has had my pants down again.
What I’m assuming you don’t understand is the bit where I said I was under her earlier and everything was doing as it should.
I can’t believe it’s anything to do with the ecu it’s something simple possibly electrical or a connector issue, but my plan now is to get it to a landy expert and stop all this guess work, I like working on her and changing parts as I’m mechanically minded but I’m no expert when it comes to electronics or wiring, although my secrets out I do have X-ray vision but that doesn’t show up wires or ecu’s just bones but you wouldn’t know that
 
although my secrets out I do have X-ray vision but that doesn’t show up wires or ecu’s just bones but you wouldn’t know that[/QUOTE said:
We do now superman....

I knew he was real..Der Der Der Der Der...
Der Der Der...
Der Der Der Der Der....... Dit Der Der!!
As quick as flash!!!! He was fooking out of here:eek::p
Click to expand...
 
Maybe I am not making myself clear either....

You can unplug the XYZ switch from the loom, using a multimeter on the continuity setting, meter across the pin-outs and move the drive selector lever and measure the results....the below image shows the XYZ switch matrix of what reading you should get at each position - make sure it is doing this as it is this switch which tells the ECU what you selected using the drive selector....

XYZ_Switch.jpg
 
Saint.V8 said:
Maybe I am not making myself clear either....

You can unplug the XYZ switch from the loom, using a multimeter on the continuity setting, meter across the pin-outs and move the drive selector lever and measure the results....the below image shows the XYZ switch matrix of what reading you should get at each position - make sure it is doing this as it is this switch which tells the ECU what you selected using the drive selector....

View attachment 143497
Click to expand...

I understand what you are saying V8 and it’s clear to me that’s what the car should be doing but iv got as far as I can, it’s time to hand it over to a land rover expert who can pin point the exact problem. Thanks for your..........errrrr advice I have a copy of rave, I was simply social networking my experiences thus far and seeing if anyone had had a similar problem!? But it’s reached the point where I’m happy to let it go to a pro who I will happily pay to poke and sniff all the bits and bobs you mention cheers again
 
Hi guys quick update, mechanic came to my house, plugged obd in blue-point I believe and it wouldn’t sinc with the Car, port looked fine, no corrosion or loose wires fuse was fine and power to the obd device.
On loading it onto the loader to get it to garage we noticed the reverse lights are on but when selecting neutral it moved freely, it’s so strange it’s going threw the gears fine but the electrical side of the car still thinks it’s in reverse.
It’s up at the garage now and I can only hope I get it back while we have all this snow, so I can enjoy myself but I won’t hold my breath. Has anyone had this exact problem before??
 
Saint.V8 said:
I would be checking the cable to the XYZ switch on the side of the box or indeed the XYZ switch itself.

The XYZ switch is fitted to the side of the box and informs the gearbox ECU what position the drive select lever is in....

Remember ATF should be checked with the engine running, in N and cold.
Click to expand...
I had same problem on my l322 4.4. It was the xyz switch to blame. The switch is located where it gets hammered by water and dirt,so change it. My present l322 became dimwitted,never knowing if it should change up or down. Told by gearbox specialist torque converter was spent. Put tube of Dr. Tranny in gearbox and it's now perfect. £15 for 2 tubes on ebay
 
Dai version said:
I had same problem on my l322 4.4. It was the xyz switch to blame. The switch is located where it gets hammered by water and dirt,so change it. My present l322 became dimwitted,never knowing if it should change up or down. Told by gearbox specialist torque converter was spent. Put tube of Dr. Tranny in gearbox and it's now perfect. £15 for 2 tubes on ebay
Click to expand...

That was over 3 years ago. I cannot imagine it isn't fixed by now but it would have been nice to have confirmation of the problem.
 
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