I sold my bulletproof XJR to a friend in April, it hasn't been so bulletproof for him and I'm trying to resolve a nagging issue he's had. Today was the first time it actually didn't function for me. It has been having physical shifting problems for him for 4 months or so on a random basis. Basically what he said is it would go into reverse fine then not shift into drive unless he fiddled with it. Sometimes he would get a gearbox fault and sometimes it would limp home mode. Sometimes it would shift just fine. Today I went over as he said it had done it again and now wasn't starting. Well I get there and first attempt to pull codes. The last time he brought it over for that he had just left the battery go flat so no codes stored. The codes today from my enginuity (that hasn't for quite some time been able to pull Jag codes so i need to get them to resolve that) so the codes are generic p1111 unspecified code p705 Range sensor p0730 incorrect gear ratio and p0560 system voltage. Battery was again flat. (good battery less than 2 years old that was checked and slow charged after the last flat). I think that whatever the issue is the car isn't going into sleep mode and then running the battery down.

So I swapped batteries with a decent battery and start it (thus clearing codes of course). Starts fine, put it in reverse than drive goes in fine. Put it in reverse back it up then try to go to drive and it functions as if the cable is broken (zero resistance to moving the shifter at all). So now I need to move the thing from blocking the alley. Won't go back into any gear at this point or neutral. It simply moves around the J aside from it won't go back into park (stops a bit beyond r going toward p) Jack it up and go under and can partially shift the linkage but since I only had a jack and no stands I didn't want to spend too much time. It didn't allow the shifter to return to park just in a limited loose range from drive to r.w Took the center console off to get at the shift cable at the shifter. After detatching it I can manually shift it to park, reverse, neutral and drive. Of course I'm getting lots of messages. i.e. gearbox temp, gearbox fault etc. I was able to drive it back to the parking space.

I am thinking there is something in the shifter assembly that isn't working right which should be easy to swap with another but now I'm trying to source one. It seems the XJR had a different linear switch than the xj8. Does anybody know if that is the case? Is it likely an issue with his linear switch? I'm not so sure what that does in the whole equation. Of course the guy doesn't have AAA otherwise I would send it to a mechanic about 60 miles away but since it is all open and 2 bolts a few screws and electrical connector away from being swapped for a junkyard one I'm happy to have him get one and put it in. Of course XJ8 ones are cheaper and a whole lot more available then the XJR versions.

Thanks for any help ya can give.

 

Short version: Check / replace the cable itself. It might not be the linear, but it could be a stretched or mis-aligned cable. I had that issue with mine, and in my case one of the joints at the end of the cable had almost seized and made it not line up properly. There's such a small margin of error in alignment too, between the cable and the switch. It took me a while to finally get it just right, but from what you're saying, it sounds almost spot-on to the issues I had leading to mine. It still could be the switch, but I'd say you'll want to get the cable completely ruled out and checked, and completely lined up properly first, make sure it's not just something simple in that regard.

 

The XJ8 transmission is made by BMW and the XJR is made by Mercedes. They don't crossover.

 

 

Thanks guys (avern you are close but the xj8 tranny is made by zf not bmw and it is the shifter not the tranny I'm talking about but your sig has me jealous and missing my lost kitties). The cable pushes and pulls pretty decently without any lever on there so I don't think it is gunked up and not moving freely. It almost seems like the shifter has no resistance at all and wouldn't move the cable at all when you moved it before i disconnected the cable from it so I tend to think it is the issue but do plan to have him clean and lube the cable up and replace with a new one if the issues come back or it is hard to shift at all.

 

Just a slight correction there.....
The XJR has a Mercedes gearbox but the standard XJ8 has it five speed gearbox made by ZF ...it's the 5HP24E
The cables and linear switches are a completely different mechanism on each type of box.

 

It was a cable on mine. Pull the ski slope, pull the PRND cover, and have the shifter just wide open. This allows you to pull the shifter further down that with the surround on and compensate for a stretched or misaligned cable. Adjusting the cable created issues getting into park, and I concluded after fiddling a bit that the cable was indeed stretched.

I left the shift mechanism all exposed for a miserable week last winter while waiting for a nice used cable to arrive from eBay. You can do it for a little while to confirm the cable; you need all that crap off to adjust it anyway; which is done in the interior and not at the transmission..

Shifter assembly and cable are different on XJRs than XJ8s. You'll have to spend the extra.

 

Funny thing is the cable is now a classic part so freaking Tata wants to pay for a boob job selling one $600 for it. No way I'd suggest he replace it if it is moving fine etc as it is adjustable with the nuts right? Now if there is specs on measuring the thing that is a different story but I'm guessing Jag didn't offer that in the service program huh. Again, when the cable is attached should the lever just be flopping around with no resistance and the cable not moving? That leads me to believe as I suspect from being able to move the cable pretty freely with my hand when not attached to the lever that it is at least functioning fine. might it be stretched, of course any cable that is 15 years old is bound to be stretched. Thanks everyone for your thoughts. Kind of in a bind as I don't want to not show concern to his plight but also know that it never had this issue when I had it. I simply wish he had listened to me and gotten it looked at immediately when it first started as it isn't drivable to a jag mechanic now that it is in limp mode

 

Check these guys out, even if you don't see it listed, ask them.

https://www.galaxyusedautoparts.com/...nden-plas.html

 

It seems to be an important item to include the exact part number you are seeking. Then if the seller claims their different part number will work, the buyer has a cause for refund, and of course return shipping at sellers cost, when it doesn’t.

 

Trevor, hope you get the cable issues fixed and I don't want to propose the introduction of additional problems or things to look at but your initial issue sounds like one my (99) XJR had.
It would be fine to back out of the driveway but would hesitate, sometimes for minutes, before shifting to drive as the lever had suggested it should (move the lever and wait).
It would also occasionally go into limp home (2nd gear only) while running around town.
Especially annoying as I usually didn't notice until I was on the highway, and the trans fault message came up..
I don't have a Jag capable code reader so I was flying a little blind.
The Merc tranny has trouble with the conductor plate that mounts shift solenoids and sensors to read output shaft speeds.
I got away with two "drain the trans and change the filter" operations and think the new fluid might have helped but the 3rd time it started happening I bit the bullet and swapped out the conductor plate.
Even though I couldn't see any cracks or obvious problems with the original swapping the plate (as well as new fluid & filter) has had the old girl shifting wonderfully for over a year now.
No more limp home issues, no more hesitation between reverse and drive, and it even seems to shift smoother thru the gears.
Prior to this it was kind of a rough gear change.
The swap is pretty simple (messy but simple) and even if you get official Merc parts not very expensive.
It could be you've got several issues to tackle or maybe just the cable and shifter adjustment but I thought I'd mention our common symptoms and how my issues (seem) to have been resolved.
Hopefully I haven't jinxed my cat crowing about a solution...

 

Hahaha… roosters don’t jinx cats…. Cats jinx roosters….especially black cats. Being down here where Jaguars roam free (real jaguars) I appreciate the name our cars bear.

 

good for me I have 2 black cats...and a red one...

 

If have the part number I can look in garage. 50/50 I still have it.

 

It is true that the shifter cables may elongate over time. It is also true that the attached fittings,
housings and channels may deform due to use, temperature and material degradation. The
most obvious solution would have been to place a length adjuster into the design I see some
indication of that in the J-gate assembly. Isn't there some way to affect the modification, without
the need for a whole new shifter cable?