Thread: Replaced my XYZ switch on my 2003 Discovery (gas model)

Well today I replaced my XYZ switch with a used one from eBay and everything for the most part seems fine. Here is a little write up of what worked for me. Thankfully my transmission is very clean so I hardly soiled my hands. I would normally wear gloves but this switch is in a tight spot where gloves would interfere and there is a need for that tactile feeling that you loose with gloves.

I first disconnected the shift cable mount plate from the transmission shift shaft using a 13mm ratcheting box wrench. I decided to also remove a small heat/sound shield that attaches to the body just to make a bit more room, it was held on with 2 10mm nuts. I then removed the 2 10mm bolts that hold the switch to the transmission and carefully slid the switch off. My goal was to avoid moving the wheel within the switch so I could align my replacement as closely as possible with the one I took off.

The tricky part is to get the plug disconnected. It is in a very tight space higher above the switch so I decided to release the shift cable from it's mount to make more room for my hands. It is held in place with a C-clip and once that was removed I slid the cable back to get it detached from it's mount and let it just hang out of the way. I used a long screwdriver to release the entire plug assembly from the metal tab attached to the transmission that holds the plug and harness in place and the cable dropped down making it very easy to pinch the tabs and remove the switch.

I took the old switch and the new one to my workbench where the lighting is better and using a large screwdriver blade turned the wheel within the replacement switch to attempt to match the one I just took out. Who knows what gear the replacement switch was in when it was removed. I eyeballed it as best I could.

Reversed the removal process to reinstall the switch and other then being a bit uncomfortable squirming under my truck I got it all back in place. I cleaned my work area (I hate when I accidentally run over tools) and started the car up. Went into reverse fine and backed out of the driveway and took a short drive. No M/S lights or OBDII code (I had cleared it prior to starting my repair) and the shifting seems smooth. Prior to my repair the lights came on almost instantly and the transmission would go into limp mode. I also had started getting a PO705 code.

Only thing I noticed is that when in Park I see the P on the dash and also in D, 3, 2, and 1 as well as the small red light next to each gear on the shift console. However I am not seeing R when in Reverse or N in Neutral on the dash or the corresponding red light on the console when in those 2 gear shift positions, but I had no problem backing up and the rear wiper also came on when in reverse and with the front wipers on. I am guessing that my XYZ switch needs a bit of fine tuning where it mounts to the transmission. Not that big of a deal to me as long as it goes into gear and I don't get the M/S lights, etc. Need to wait for my son to come by to readjust the switch.

Just a final thought on the switch I took out. The overall shape and configuration is the same but there are very slight differences with the one I put in, maybe some small design changes over the years. Mainly the plastic part of the housing is bit different. My vehicle is a 2003 and the one I got to replace I believe came out of a 2001. Also the corrugated plastic sleeve that shields the wires was cracked and broken, I wonder if this is how water gets into the switch. There does not look like there is much of a seal where the wires enter the switch. On the one I installed I squeezed some RTV cement there to seal it better and also wrapped the entire plastic wire cover with black electrical tape. And from what I can tell, the AC drain drips right above the spot where the wires enter the switch. Seem like this would be the more likely way that water enters the switch over time.

I didn't bother to reroute the AC drains at this time as the small nipples that come into the transmission tunnel would be hard to attach something to. I think one would need to get at the drains where the exit the AC unit in the vehicle to attach some tubing. I'm hopeful that with the wires sealed with RTV I should be able to keep water out.

Hi all and thankyou for the quick response, well yes I have contacted the Airtex company and they will not post to Australia, but they gave me another supplier Auto Spare Parts USA, they do have one but at $624 plus postage it's again not viable and then you have to wait for it to arrive, anyway I'll have to bite the bullet and go to ULR Landrover in Malvern and buy a new one for $705,,also I did disassemble my original switch and I could not see any corrosion on the small copper contact strips? I also extended the air con drain hose by removing the rubber nipple from the end and inserted a black rubber hose inside the old one rerouting it far from the switch eliminating any possibility of water ingress, thankyou all, Peter