OK, sounds crazy right?

Well this is clearly some kind of an electrical issue but it goes something like this:

Over the last two weeks I started having an intermittent speedometer irregularity where all of a sudden I would notice that it wasn't reading high enough. It would slowly drop lower and lower and then to below zero. When I came to a stop you then see the needle twitch a bit and make a noise almost the same as in older cars when you had a problem with the mechanically driven speedometer cable. A tick, tick, tick that stops when the car stops.

This goes away once I turn the car off but eventually after long enough drives it returns.

The car drove fine and the cruise control works properly as well. I tracked my actual speed with the trip computer's average speed and that always worked correctly.

So the car knew how fast it was going.

Then the symptoms spread.

Up next was the tach. One day I noticed that the rpms were unusually high for the speed/gear and noise I was experiencing. Oh crap!

This too disapeared when I restarted the car. I had a one hour drive at redline one day!

Then yesterday I noticed that the rpm gauge was now stuck at 8,000 when the car is off. So when I'm driving it looks to be way past the marking at an estimated 10,000 rpm? Hey I'm just getting ready for F1 racing which is actually coming to NJ next year run on the streets a couple of miles from my house! I guess my Jag heard about this too?

Seriously, I think the needle has rotated on the shaft of the meter from when it was driven way past it's normal stop point?

The other electrical issue I had with this car is well documented in this thread:
https://www.jaguarforums.com/forum/s...ighlight=kitty

That issue ended up with a recently replaced battery being defective and another new battery is now in place. So this not a tired battery issue.

I've also started to notice a slight noise in what I think is the 3->4 up-shift that sounds a bit like a yelp. I think there's some info on this but I haven't researched that as yet. I'm guessing it's unrelated.

But it looks like my instrument cluster has lost the tach and speedo functions on the analog gauges. I believe the car is detecting the actual the speed and engine rpms properly.

Has anyone ever heard of this issue before?

I see no water in the trunk. Maybe it's a very slight amount?

Thanks.

 

Among other things, it could be a loose cable or defective cluster. Try it in ETM (Engineering Test Mode - Search should get you info) and see whether the values look OK but the needles aren't, or what.

BTW, batt volts is one of the items

jag-specific OBD can interact with the ICM (inst cluster module) but that means AE or IDS/SDD/WDS etc. I suspect ETM will tell you enough for now.

Any OBD tool will let you read the PCM and get such as RPM. It'll tell you it's OK, though, or it wouldn't drive OK.

Any gearbox thing is separate. The ICM is essentially a slave (to PCM, TCM, etc).

 

Yes I can try ETM.

There's nothing wrong with my battery.

I already know the gauges don't match with reality but the trip computer and cruise control work properly so what would I be looking for?

I'm hoping a Jag tech has seen something like this already and will comment?

In any event, the instruments cluster is going to have to come out. Oh joy. This sounds like a dealer job to me. Probably a new tach is on the list unless the needle can be reset?

I ignored all the warnings from my friends about Jags and electrics ...

This is one of the flakiest cars I've ever owned. Unfortunately it's also very complex.

 

Sounds like corrosion at a wiring harness connector or juncture, or a loose or corroded ground.

 

If it is not a wiring or connector fault, unless your car is still under warranty, your best bet is probably a used instrument cluster from ebay. The dealer will not repair the failing gauges, but want to swap out the entire unit, and a new one will be very costly.

WIih proper documentation I believe your dealer can reporgram the odometer to your actual miles if needed.

There is nothing inherently unreliable about Jaguar's instrument clusters, it looks like you just got the short straw on this one unfortunately.

 

ETM will show a lot of what is and isn't working. Look at what happens carefully.

It will also (attempt to) reset the needles....

 

Thanks guys.

I noticed a couple of used clusters on eBay this morning.

But first I need to lookup getting into ETM and see what I can make of that.

Anyone know how difficult it is to remove the gauges?

Looks like a pull of the wood veneer fascia and then ... ?

 

Test mode did indeed reset the tach.

So ... is it a harness/ground issue or the gauges?

If I get a replacement set of gauges off of eBay and I'm able to install them myself?????? then any repetition would point to a harness issue I guess.

 

[QUOTE=JagV8;522523]ETM will show a lot of what is and isn't working. Look at what happens carefully./QUOTE]

So do you have any specifics as to you think I should be looking for?

I'm assuming I would engage ETM observing the relevant parameters and then drive the car until a failure is observed.

 

If everything is working after the ETM reset, it is possible it was a 'soft' failure in the cluster computer or stepper motor driver chips - basically akin to a computer crash.

Drive the car and see if it recurs...you might have gotten lucky!

 

I could use some lucky ...

I'm taking the thing on a long trip in the middle of June. it would be nice if this wasn't still annoying me.

 

Were the values (those you can figure out from previous threads here etc), displayed as you step through them, garbled or believable? Do they change in a way that makes sense? E.g. temp increasing as engine warms, volts up when you raise revs, and lower when engine off? At the pain and cost of swapping ICM I'm thinking it's worth your while to spend time in experimenting intelligently....

Are needles back as they should be?

 

The transmission upshift "yelp" as you call it is the well-known and annoying "ZF bark". Our 2005 S-Type barked from time to time back in the late summer and early autumn of 2010. As the weather cooled, the bark ceased and has not returned (knocking on wood). The car currently has 70,600 miles....

Jaguar used to sell a one-litre bottle of Lifeguard 1 (about $43 when it was available) containing some super-slick friction modifiers. The fix was to drain one litre of ATF from your ZF pan, then pump in the one-litre bottle of Lifeguard 1. It would magically keep the clutch packs from grabbing and making the quick bark noise upon acceleration. But Jaguar no longer sells it. Their current recommendation for the ZF bark is to do a complete drain-and-fill of fresh Lifeguard 6, which now supposedly has the super-slick friction modifiers that Lifeguard 1 contained mixed into it....

If you can find Lifeguard 1 elsewhere, you may want to try that one-litre drain and fill fix. Perhaps Land Rover still sells it since they sell Lifeguard 6 for their vehicles....

Both Jaguar and ZF have told me that the ZF bark is simply an annoying quirk that will not damage any transmission components even if it continues for years. I hope that is indeed true, because many of the 6-speed ZF-equipped cars suffer from the bark from time to time. And not just S-Types. XJs and XKs as well....

 

A jaguar that barks like a dog ... got it!

Thanks Jon. Now that discussion is coming back to me.

Is it even feasible to suck a liter out of the fill tube? I've never even looked for one. How do you drain one liter?

 

The needles are back but I'll have to go through this again and read the pdf instructions thoroughly to see what the two values displayed under the RPMs and speedo diagnotics mean.

I'll want to observe this during a failure condition as opposed to a normal operation. I may get an opportunity tomorrow.

 

Worth a try. If it keeps going silly then I suppose disassembly of the dash will be needed even if you're just looking for a loose cable (or mouse chewed cable or damp or whatever).

I don't see why you (or a trans shop) couldn't suck trans fluid out and replace. Access is a bit awkward.

 

Here's how I was going to drain a litre of Lifeguard 6 out of our S-Type before it quit barking:

1. Take an empty one-gallon opaque plastic milk jug. Cut the spout off, and enlarge the opening to the point where you could hold it under your ZF drain plug to easily catch a stream of draining fluid.

2. Get a metric measuring cup. I found one in my wife's kitchen stash of cooking implements. Pour one litre of water into the empty milk jug. Set the milk jug on your kitchen table. Using a black magic marker, trace the top of the waterline all around the outside of the jug. Pour the water out of the jug. Now you have your one-litre catch pan.

3. Lift the car safely, get under it, and first ensure that you can loosen and remove your ZF fill plug. Catch any draining ATF in your milk jug. If it stops short of a litre, and it probably will, slowly open the ZF drain plug to continue draining enough total ATF to reach the one-litre mark on your jug. Tighten the ZF drain plug once you have drained one litre.

4. Follow the usual refill instructions on how to pump fresh ATF into your ZF fill hole. You have to start the engine and allow the ATF to warm up some. Forum members "ccc" and "joycesjag" have written excellent step-by-step procedures on exactly how to do this. You'll need a hand pump with a tube that fits into your ZF fill hole. Forum member "Reverend Sam" has posted a video on his Youtube channel that shows how he refilled his former XK8's ZF. Exact same transmission, so it is well worth watching.

If you find a supplier of Lifeguard 1 and decide to do this, be sure to post your experience on the forum. There are still a couple of owners who want to do this in an effort to quiet their ZF bark, but they have been unable to find a source for Lifeguard 1....

 

The tach failed again tonight during a short drive. No results top report though as you have to put the car into ETM before any such failure as the first thing it does after entering ETM is reset the gauges whether you want to or not!

 

Well I tried Google for lifeguard 1 but this is all I came up with ...

 

If it'll stay faulty you might try at that point communicating via OBD port and failing that then checking for proper CAN bus termination. You'd need at least AE and a DVOM to do those.

Instead or as well, I suppose take the ICM out. Probably JTIS will be good enough as nothing much changed other than the cabling connectors etc. If it then turns out to be a loose plug, things will be relatively simple but if the ICM's gone bad internally, maybe just a bad solder joint, shops don't seem to mend anything even trivial issues like that. I guess you'd need a tech who knows about reprogramming an ICM.