Discovery 2 TD5 M+S Lights Flash Black XYZ / Inhibitor Switch Removal, Refurb and Replacement how to

I went to start the truck and had the dreaded green M+S lights flashing on the dashboard (and limp mode previously too) and it wouldn't start, so checked the battery voltage/terminals that was all good, so tested the gears and it wouldn't show some of them which lead to us a faulty XYZ / Inhibitor switch other issues can cause this though. Currently these switches are £700+ in the UK to buy so that wasn't going to happen, and £50 to be refurbished Nov 2022. Previously I had noticed that sometimes the truck wouldn't start by key after using it, then would be fine until the switch stopped working.
Make sure the exhaust is cold or remove it first. The switch is located on the side of the gear box, has two 10mm bolts and the gear level cable attached via a link. It's difficult to get to and you can remove the exhaust downpipe but we chose not to, the switch has metal aluminium and black plastic parts which are riveted together, you can drill those out with a 4mm metal drill bit. As it's a rotary switch there's a part that moved with the gear box shaft and below that there's several metal tracks that the switch contacts with at different positions to tell the computer what gear you're in. When we removed the part that turns, it has four copper fingers with others with little metal pads and one of the pads had electrical arcing so was lightly sanded along with some gentle brass wire brushing in other places to clean it up. After that we used plenty of electrical contact cleaner and wiped it all out, and applied a little dielectric grease to the plastic parts which move which previously had some then resembled the switch with rivets, but you can use little bolts with nylock nuts. Just make sure everything is super clean, and if needed bend the copper fingers a little to ensure they have good contact otherwise the fault can happen again but be careful and don't damage anything.
When it comes to refitting the switch you need to follow a procedure, which is leave the gear lever in the P position in the car, then on the gear box shaft move it all the way clockwise to the engine then two detents (clicks) anti-clockwise to the boot/back of the car you will hear two clicks you can use the gear shifter cable arm to do this safely, some say use piliers but you risk damaging the shaft so not advised.
On the switch where the gearbox shaft connects it has a lots of little splines and a flat part which matched the metal shaft design, don't touch the spindle position just place the switch carefully over it (super clean and some grease/silicone can help), and make sure it sits all the way back then put the top and bottom 10mm bolts in, you can leave them a little loose for fine tuning but we didn't need to, but this handy if P is flashing on the dashboard then you can get somebody to tell you this and then turn the switch side to side until it's solid then tighten up. The gear level cable also needs to be reattached, if the gear e.g. P/N are solid and the M+S lights are flashing reset the ECU by disconnecting the battery for a few seconds, I cleared the fault codes on my OBD2 computer. There is a alignment tool, we didn't use it it but it's around £20-30 the instructions out there along with the haynes manual do say to use.
If you refit the switch and tighten the bolts it keeps flashing in P then it's not on the gearbox shaft properly, we had this issue so take it off and put it back on carefully just make sure it's clean and try again, remember the gear indicated on the dash and LED lights either side of the lever must be solid not flashing otherwise the switch isn't in the correct position.
We hope this video helps, and wish you luck if you have this issue yourself as we did struggle with access a little it's not easy. You will need a small 10mm ratchet, 13mm spanner, light source, dielectric grease, 4mm metal drill bit, rivets/bolts and electrical contact cleaner. Also consider using penetrating oil on the bolts and also a small wire brush to clean surfaces up as you don't want to slip or shear anything off as that would make this job even harder than it already is due to access.
If you have any questions please ask us, I will do my best we hope our experience and write-up above helps you out.
#discovery2 #discoverytd5 #disco2

[@ableliondotorg4611]

and THANK YOU for your thoroughness and attention to detail -- for this job, nothing else will do!

[@DanielJohnHowTo]

You are very welcome

[@bobbutcher7725]

Brilliant video guys. Good practical advice, easy to understand and in a language, and a tongue, I could understand. No disrespect to other videos but when instructions are delivered in a foreign or non 'proper' English voice, I struggle. You chaps are realistic, informative and your presentation is not full of bull***t. Go to the top of the class.....👍👍✴✴ and have a couple of gold stars too.

[@DanielJohnHowTo]

Thank you.

[@bulletboy4288]

Hi guys, just a note, these switches also power the reversing lights and this can cause the track to eventually fail where you continually swipe through reverse from park to drive. I fitted low power LED reversing lamps as this will effectively reduce this load and help prevent arching/wear. My car (98 model) does not have the park/ignition interlock, this allows me to leave the transmission in neutral and remove the key, I just use the handbrake, again this is less action on the switch (worth exercising through the PRND321 range periodically though). I have only once had the M&S lamps up and that was the following morning after a very heavy rain M1 journey, if cleared after a few minuets as I think the exhaust dried it out but the TCU will remember any fault until power cycled, it has not happened again but I would worry if I were to do any deep fording or another rain sodden journey. All modern automatics have these switches but the Land Rover one does seem to be susceptible to problems, I ran a 2001 shogun for 5 years and no issues,,,,,,,,,,,

[@DanielJohnHowTo]

Thank you for sharing this information.

[@williamandrewbaker3566]

After all that did it drive how it should, now I’m going to do mine today wish me luck, ps, I’m 75,

[@DanielJohnHowTo]

No issues at all, and driving as before thanks and good luck.

[@alantate1287]

Hi is this the same for my discovery mk1 . there seams to be very little room to work, but I hope to do this job myself , your video is very helpful

[@DanielJohnHowTo]

Thanks for your comment, it could be the same but I can't say 100%

[@pierrejeanes]

Wow so the switch mechanically switch the back lights ? , I would yhen put a relay between so the load is managed by the relay instead of that poor switch

[@jacklister3653]

Great video, just a question so you turn the shaft clockwise till it stops clicking then then anit clockwise twice?

[@DanielJohnHowTo]

yep, clockwise to the engine then two clicks back to rear, you can align it but if you have any trouble look at "Laser 6485 Alignment Tool for JLR Automatic Gearboxes" it makes the job a lot easier from experience.

[@DanielJohnHowTo]

by align i mean then place switch over spindle, and you don't want any lights e.g M+S flashing and also the gear position is solid.

[@jacklister3653]

Does it have to be in P for all of it?

[@ableliondotorg4611]

Hi I can't find the document that is referenced at the listed URL... can you make it available? THANKS

[@DanielJohnHowTo]

which one are you looking for?

[@PaulFeetham]

Will a faulty switch stop the car from starting?

[@DanielJohnHowTo]

yes it will

[@danvitesse]

My disco has started triggering the M S lights if i transition from P to D to quickly or if it doesn't quite seat proply in a selected gear. It will even trigger the M S lights if i wobble the selector slightly I dont believe the XYZ switch is the problem as i have no loss of power and the vehicle never fails to start. If i switch off the ignition when i start the car again the lights disappear could this be an alignment issue or has something come loose i wonder?

[@DanielJohnHowTo]

Thanks for your comment, it could be a few things. I'd start with the battery voltage check, then make sure ECU plugs don't have oil in them then you could look at the wiring loom on top of the gearbox for the XYZ switch for bad wiring if you don't think the switch is at fault. If you do ever take the switch off buy the laser alignment tool, it saves so much time and hassle.

[@danvitesse]

@@DanielJohnHowTo Thanks much appreciated. I now suspect its the contacts in the XYZ switch breaking down due to age/corrison as in your video. I climbed under the disco last night and leaving everything in SITU sprayed WD40 into the switch this seems to have fixed it for now :)

[@pawem3160]

Too much talk too little work. Not everyone knows English. A little more practical work would be nice.