"1989 XJS Update" factory documentation

Apologies is this is a repost. I’ve never seen it before.
As my car is an 89, I found this document interesting. Lots of detail on Teves III, speedo interface, etc.


An unusual level of clarity for a Jaguar publication.

I have all the XJ-S updates from 1988 to 1996 that I downloaded in .pdf when I worked at the dealer.

I also saved many of original paper booklets of the updates and introductions.
Some of the publications include Engine Performance and S64_XJS Coupe and Conv Body Enhancement from the late 1980s.

S80_XJRS Product Support is interesting but I have never worked on the XJRS.

I don’t know the file size limit of this forum but I’m sure that some of the large files won’t fit the limits.

I found the rom and the tech updates years ago at a website maintained by a jag enthusiast. Free downloads. All he did was ask for donations to help maintain his webpage. Wish I could remember what it was

Much of the information on the body structure of the newly introduced convertibles, the Teves III, etc., IN COLOR, was posted by yours truly back in the day.

A tribute to the albums on the “old site”

I have not heard from Jim (Griffin, from Florida) in years. Wonder if he is still on the list.

Yup, they’re pretty good. I have several. As far as I know they’re specific to USA market cars. I think the USA dealers eventually put some pressure on Jaguar to provide some decent technical literature. Thus the S57 wiring diagrams, S58 Engine performance guide, etc


I found an app for my Android phone that can significantly reduce the size of pdfscwith no perceptible loss of quality. I reduced the S58 Engine Performance pdf from 17mb to around 1.6 mb. The app is called “Compress PDF files”. It’s ad supported, but it does the job.

How do I go about looking at the photos? Most come up in a very small thumbnail which I cannot open.
Some do, but most do not.

The photo albums that were invaluable part of the “old” jag-lovers forums have not been migrated to the new one. As a result, most of the information is not visible on the modern and supposedly more user-friendly forum platform.

There is a workaround, but not simple. Here:

Looks like most of the changes had to do with the braking system, by far.

Wow, just had a lightbulb go off in my head. Back with the XJ40s (pre-'94 MYs) we had to contend with that troublesome “green blood” = hydraulic brake system mineral oil, used in conjunction with the actuator. I never stopped to think why our facelift XJSes still use an actuator, but no more green blood involved. :confused: So, with the facelift models, the actuator instead acts on the “regular” brake fluid to assist pressure. ? :confused:

btw, re: that speed interface module - I often wonder if mine is blinky and, if so, maybe that explains why my speedo needle often “vibrates” or quivers slightly at speeds in the 30-40 MPH or so range. A couple of years ago I tore into the relay/module bank on the left side of Superblue’s boot, looking for the infamous anti-slosh module after my gas gauge started acting up on taking sharp curves and such. While looking in that area, I found an old S.I.M. laying in that storage compartment on the left side of the boot. It looked like the PO had pulled it and cracked the case, apparently trying to pull out the internal circuitry to tend to something ailing with it. Evidently he eventually gave up on that idea and bought a replacement module, as that was in its designated slot in the relay/module bank. :thinking: Again, I’m wondering if now the replacement unit is acting up. Is that common on a facelift with less than 80K miles (at the time)? Is there an EZ way to test it? :confused:

Same problem here. I guess that installation of the latest version of “Discourse” on here didn’t help such issues. ? :frowning_face: