Hi. First time contributing here but you guys are a great help. Anyway, I bought an 88 Vanden Plas a few months ago and the instrument cluster was a christmas tree on a good day. Most of the time it wasn't working at all. I took it apart and soldered the power board and fixed most issues. However, it was still unpredictable. So, I stumbled across this thread and was inspired to swap mine.

I found a 91 jag at the junk yard and bought the cluster and then started researching online for wiring diagrams. Not an easy find! But, I was fruitful in the end. Anyway, that brings me here. Your wealth of information and inspiration inspired me to share what I found.

With these diagrams, you need nothing else. I just finished my swap based on these diagrams and have no glitches! ...and a much better looking cluster in my baby!

However, one tricky install is the vcm. I resolved it by also swapping the vcm from a 91 jag. Just remember, the vcm from the 91 has one connector and the vcm from the 88 has two connectors. What I did was swap the vcm, then splice the two connectors where the one connector was. The diagrams tell you exactly what wires go where and everything, including cruise control still works flawlessly.

I hope all of this helps, as you guys have helped me countless times on this site.

 

Also, I forgot to say, I have the 88 cluster that I swapped out for sale. I am going to put it on ebay for $30 plus $15 shipping. If anyone is interested, I will sell it for $30 plus whatever actual shipping is.

Like I said before, it works but is undependable. It has all the connectors. Let me know if you are interested. It is being sold as is, with no return or refunds. Thanks.
mr_determined at the hot mail

 

Item is no longer for sale!

 

A great conversion. Someone should develop and market an adaption loom - I'd buy one.

 

the diagrams are the best. Thanks

 

You're very welcome.

 

Hello! This is Wendell Jones. Thank you for the information you provided. I have a similar issue. I have a 1989 vandan Plas and the instrument cluster gauges have stopped working also. The oil pressure, water temperature and speedometer do not work. The techometer is the only gauge that seem to be working. I have checked all fuses that I can find and all are intact. I wanted to upgrade to a MY 1990 IP but was unsure if it was possible. Now I see that it is. Thanks !

 

The information about the VCM is icing on the cake.

 

Massive respect to all who contributed to this thread.
This is the right stuff!

I have the skills and maybe access to the surplus looms required to do the 1988-1990 instrument loom fairly tidily, (I do radio looms on aircraft from time to time) if anyone would like to cross my palm with silver.

I can also do a complete interior "rebulb", on the XJ40 (with cleaning of the exposed car interior areas/joins) using all new matched bulbs of the correct voltage/amperage to give the best chance of another 10-15 years before they start to go again...

I hope no one objects to me putting this here, but someone did suggest upthread that there may be a need for commercial manufacture of the upgrade looms, and I am told that due to problems sourcing the bulbs, plus the fiddliness of some of it, not many people can do the "rebulb".

I'm currently working on a trick to allow the petrol guage to indicate the contents of the LPG tank correctly when I switch over. Not important, but I hate the LPG LED display, and they always fit them somewhere really naff... Think I'll need to use an arduino nano to translate between different LPG sensors/tank types to get the scaling right, but if I can manage it at least the VCM "range" function may work better on the gas...

 

Thank u very much for such a great job , well I have the same problem, have the 2 instrument panals, but I couldnt connect , can u please just send photos showing how to connect the 4 socits into 2, wire collors are diffrent , I tried to zoom to the photo
but no good, just show witch wire from each plug to be connected to witch wire.. from the other plug.. if possible,. Thank u soo much
Basel

 

Hi Basel,

Welcome to the Jaguar Forums! It's great to have you with us!

Please note that the post you quoted is from 2011, so this is an old thread. Hopefully you'll still receive some helpful replies.

Also, since we're a friendly group, please visit the New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum and post an introduction so we can give you a proper welcome and learn something about you and your Jaguar.

Cheers!

Don

 

Message #21 in this same thread has some wiring diagrams. If you look at the wiring diagrams and follow the contacts, the colors of the wires become unimportant. Each wire connects to a specific place on the actual plug. Each plug is labeled (A1, A2,.... B1, B2,... ). In other words, follow where the wire connects to the plug, and connect the wire to its proper functiion, and the color becomes irrelevant. Hope this helps.

 

[QUOTE=Trick Freestones;390924]NOTE: MY stands for model year, icydk.

I found some time to get back to work on this.


a pic found on the Internet of a functioning 1988-89 XJ40 Vacuum Fluorescent Display Instrument Pack

The vacuum fluorescent display (vfd) Instrument Pack (IP) in my 1988 XJ40 went south. The speedometer and tachometer work but the only thing that works on the display is a flashing orange rectangle in the VCM area.

Quite frankly, I was reluctant to drive the car much in this condition; only the speedometer and tachometer worked. I had NO idea if the alternator was charging the battery, how much gas I had left in the tank, if the engine was overheating, or how much oil pressure the engine had. Worse still, I had no odometer reading and thus, could not get the car inspected in this condition.

What to do?

After ensuring the behind dash electrical plugs had power where needed, I decided the IP was toast and went searching for a replacement. I found from a search on the Internet that these vfd clusters were troublesome and prone to failure. I found several on eBay, but they were expensive. Plus, there was no assurance that they, too, wouldn't die in a short period of time after putting it back into service. Mine had 118K on it and the ones I saw for sale had even more miles on them.

From my research, I found that the 1990+ MY XJ40 Instrument Packs were upgraded to analog gauges. If these go bad, it seems one could just swap out bad gauges for good ones out of another IP.

Perusing several wiring schematics, I found most of the requisite wiring was in my 1988 harness; it was just spread over 4 connectors which were quite different from the two used in the 1990+ MY packs.

I found little information on how to accomplish this task on the Internet. The most I found was that "someone posted somewhere that someone told him, that it was possible". WTF?

So, I subscribed to the old adage, "where there's a will, there's a way" and pushed ahead with the idea.

If the reader decides to go this route, I strongly advise him/her to shop for the required parts. The prices vary widely.

I bought a 1990 Instrument Pack (IP) from eBay for $40 + shipping. I found another locally for $10. I also found two more mal-functioning 1988-89 IPs for another $10 each.


found eBay pic of the back of a 1988-89 XJ40 VFD IP showing harness connectors

You are going to need a junk 1988-89 vfd IP in order to cut several of the connector plugs from it. There are four. You may want to use your faulty one ... or get another for a donor.



You are also going to need the two plugs that fit into the back of the 1990 IP. I found my 1990 plugs for $10. They came with lots of wire because I clipped them myself from a junk car. You will need at least the parts labeled 1 and 2 (and prob 2a) found in the above pic.[/QU

Hello all. New to the Forum. I am curious if anyone out there makes or would be willing to make a gauge cluster adapter set of pigtails. Wanting to swap to the 90-94 type. I have the 89 Digital and it does what they all do. I'm not to worried about the resale value if Ido the swap. I've had this car all my life and will never sell it. if so let me know. Thanks!

 

Hi Austin-89-VDP,

Welcome to the Jaguar Forums! It's great to have you with us.

If no one offers to make pigtails for you, you may be able to figure out how to wire in salvaged connectors by comparing the wiring schematics for the '89 and '90 cars, which you can download here:

Jaguar Electrical Guide 1987 - 1989

Jaguar Electrical Guide 1990

In the meantime, please visit the New Member Area - Intro a MUST and post a required introduction so we can learn something about you and your Jaguar and give you a proper welcome.

Cheers,

Don

 

Thanks!