1994 xj40 Teves ABS elimination-is it possible?

XJ40
1

Hello all. First off a bit of info. I have a 1994 xj40 that I’ve owned for about 4yrs now. In that time I’ve dealt with many issues from the minor (burst radiator hose) to the major (interior wiring harness replacement) & everything in between. Unfortunately my beloved jag has been sitting for the last year because I’ve been having problems with my ABS system, as in its non-functional.

Before you tell me it’s my accumulator sphere let me stop you right there, I’m way past that step in the process & have already replaced it, along with the pressure switch, pump, & relay. That was back when I had a properly operating ABS system & I did so because the sphere was losing pressure (relay clicking on after only a few presses of the pedal, motor running with car in park & idle etc) and that cured that, but now a new problem arises…NO ABS FUNCTION & NO REAR BRAKES!! I have both brake & abs warning lights & VCM says fail, or pad fail depending on its mood. Also fuse 5, whatever that means, I only have 3 fuse boxes like everyone else.

The teves blink test gives me a code 21 (main valve). I am unsure if there are more codes as I can’t get past this initial code (teves blink test gives one code at a time starting with the lowest number & won’t give the next code until the current one is cleared). I own the JTIS and have gone through all of the checks in the ABS section (something like 38 separate tests) and everything but the main valve checked good-no voltage present at the terminals. I’ve tried to replace the valve block hoping the problem was in there but it made no change in performance. My fluid looked like it had never been changed so I drained the reservoir & put new fluid but that did nothing since none of that fluid went into the system. It was about that time my wheel bearing went out & I bought a Ford Ranger to drive around.

Back to the subject. I’m sick of this teves system, it’s a huge pain in the neck, doesn’t work for crap, and I can’t find replacement parts to save my life. Is it possible to eliminate the teves system & replace it with the vacuum actuated system from say a '95 x300? I’ve seen a ton of stuff about a kit you can buy for an '89 but nobody ever mentions a '94. Surely somebody out there has scrapped their teves ABS system for something more reliable and I want to know your secrets.

2

Chris,
On a '94 XJ40 “Fuse 5” is a failed fuel pump relay so I can’t imagine what that has to do with the ABS system! On earlier models, “Fuse 5” did indeed indicate a failed ABS pump relay in-line fuse but on a '94 that fuse is incorporated in one of the fuse boxes.

If you’ve replaced everything else as you indicate, I can only think that the problem may be in the ABS ECU (BCM in Jag-speak).

Obviously having no rear brakes irrespective of an ABS fault is consistent with lack of brake pressure because that is essential for them to operate.

“Code 21” may be misleading. From memory, that code is always flagged whenever ANY fault occurs in the ABS system and does not necessarily indicate a failure in the main valve itself.

Sorry can’t help with suggestions for ABS removal.

3

Thanks for the info Bryan, I guess that fuse 5 was that fuel pump relay. I did have problems with it before I swapped it out a while back.

On another note I have swapped my ABS ecu with a spare but no change & I figure that the whole system is gunked up pretty good as the fluid is black as night.

So rather than fixing the Teves I’d like to swap the entire abs system with something more reliable, I keep thinking a 95 x300 would work as a donor. That’s the year they went back to a vacuum actuated brake booster.

Somebody’s GOT to know…

4

There is a company that sells a hydroboost conversion for the Teves system in Jaguars.

I’ve no hands on experiance but it might be a viable path to resolve the lack of parts and service for the Teves system.

www.powerbrakeservice(dot)net

Not exactly inexpensive and personally, I’d probably try a wholesale swap from a breakers yard used parts supplier but still, the hydroboost option has an appeal.