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Wifes out driving the car today, sent me a video showing the gear selection acting really oddly.

The lights dont line up with whats selected, and they jump about a bit randomly as you cycle thru the gears.

I presume theres some sort of position switch involved here? Where about is it likely to be and is it likely just a bad switch or potential wiring issues?

It does seem to be driving properly by all accounts despite drive and reverse both showing "3", and its also starting just fine, despite Park showing "2"

Cheers

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Sounds like the XYZ switch might be failing, or just need its connections cleaned up a bit. IIRC the inhibitor switch is part of the gear selector itself, and the XYZ switch just tells the ECU what you're trying to do. If the gearbox gets really unhappy with this state of affairs it'll go into limp-home mode and only give you 3rd and reverse.

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xyz switch needs looking at. They're riveted together, but you can open them up and put bolts back on. there's also a breather hole on the earlier ones which you could just try and blast with contact cleaner first. D&R showing 3 shouldn't be possible (as all 3 micro-switches need to work to display 3), but anyway, take a look... Maybe get a 2nd hand one off ebay that you can bolt on while you fix yours. There are a few types, and they look very similar, so make sure you get the right part code.

Also, if you have any starting issues before you manage to fix the switch, fiddle with the gear selector until you find something that the dash says/thinks is P or N...

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Quick clip of her shifting:

https://youtu.be/NMWhOs6iqUA

You can see P = 2, N works, Reverse and drive seem to show 3. 1st seems to show 2 as well.

Oh, and it happily starts in P with "2" showing on the gate.

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There is a table in Rave that tells you what combinations of the various switches inside give each gear display. My guess would be one of them isn't working as well as it should do anymore. Possibly down to it being full of crud that you may get away with cleaning out, mine I found one of the contacts had lost its springy action and wouldn't reliably select drive as a result, leaving it with a combination of refusing to start at all, and going into limp randomly which gives you only 3rd gear to use

The part your looking for will look either like this one, or similar
https://www.ebay.co.uk/itm/Range-rover-p38-xyz-switch-grey-plug/274091850407?hash=item3fd125baa7:g:ii0AAOSwj85YRHeF

You might find a repair service for the one you have - here is one example though its for a Disco rather than p38 so you'd need to identify your switch first to see
https://www.ebay.co.uk/itm/REFURB-SERVICE-discovery-2-xyz-switch-/362520920489?_trksid=p2385738.m4383.l4275.c10

Its a little fiddly to remove, but not too bad, the suggestion of getting another one whilst you fix yours isn't a bad idea though so you can keep the car able to move.

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The results you've got are a bit odd and don't show one switch not working but switches closed. There is a breather on the top of the switch that should have a tube attached but it often falls off and allows condensation from the AC to drip directly onto it filling the switch with water. I'd suggest taking it off and draining any water out of it then putting it somewhere nice and warm to dry it out and see if it sorts itself out.

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yeh i looked at the table, and like roman says, it doesnt make much sense. For P to show as 2 that requires Z to be stuck at 0, For drive to show as 3, that requires X to be stuck at 0. But neutral works and that requires both Z and X to be set to 1...

She says it said Gearbox Fault when she went out in the afternoon, and wouldnt move in D at all until she cycled it thru all the gears, and then it worked. Shes just got back in to come home and its all back to normal with gears showing correctly and the gearbox fault message has gone.

Yey.

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When the gear position reported by the XYZ switch doesn't match the physical gear position at the gearbox cable , then you will get gearbox fault and it goes into limp home mode. So no Sport button and 3rd or 4th gear only (depending on whether it detects the fault while moving or stationary). The odd thing is that you are able to start the car when it is showing anything other than P or N. The output from the XYZ switch drives the LEDS next to the gearlever but it also tells the BeCM what gear you are in so that can display it on the dash and decide whether it should allow the starter to turn or not. Unless it is seeing P or N, the starter should be inhibited..

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Re the eBay link above, don't go by plug colour only, there is more than one type with a grey plug...i made that mistake, cost me a week, and an extra few sessions under the car in sub zero temps trying to figure out what the hell was wrong. You need to do part no's...to deal with a breaker you will probably need the zf part numbers which are stamped on. My 98 took an 0501 210 740. The incorrect one I got (grey plug, no breather) was 0501 211 036. Biggest difference is the foot length of the Ali casting, electrics are the same, but it won't fit and gear change properly

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Mine did something similar I just thrashed it between P and 1 repeatedly, that did the trick ;)

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another 100 miles yesterday and no issues at all....

I hate problems that fix themselves :(