Zel's Fleet Blog - BX, Jag XJ-S, Sinclair C5, Mercedes 208D & 230TE, AC Model 70.

[white exec]

Zel,
You said all the gauges are reading slightly low. Something common to all?
How is the car's battery/engine running/idle speed voltage?
The same figure at the instrument cluster?

https://forums.jag-lovers.com/t/1983-ja ... low/357750

https://www.jaguarforum.com/showthread.php?t=70473

[Zelandeth]

Apparently the cluster has already had a local ground fitted to try to address the issue with things under reading.

Given how common connection issues seem to be on the panel itself I'm tempted to pull it out and come up with a more electrically robust solution to the screw terminal connections between the flex PCB and the gauge modules themselves. Depending on what the posts are made of I do wonder if they could be soldered carefully.

Basically the voltmeter, fuel gauge and temperature gauge all underrread by roughly the amount shown in the photo of the fuel gauge taken a couple of posts back. This has apparently been an issue on this car for years.

I did test the resistance of the oil pressure sender but if course can't find the bit of paper with the readings on now!

[Zelandeth]

The perpetual light drizzle this afternoon put paid to any plans of doing anything outside. Nothing to stop me doing a bit of interior work though.

It's no secret that the warning lights on the dash in the XJS are rather sub par. Most of them quite simply aren't bright enough. The ones for the indicators are probably the worst. Especially as they're half shaded by the internal baffles so only half the light actually gets properly lit.

I have a bag of a couple of hundred flat top warm white LEDs and this seems like a good job for them. I'm not using coloured ones as I just don't think that will look right.

Conveniently I also have a full set of dashboard lamp holders of the correct type that I scavenged from a scrap car years ago, so it was a simple matter to solder an LED and resistor in to one to create a test unit to try out.



Here's what the lights on the dash for the indicators look like as standard.



That is how weedy it actually looks in person. On a sunny day they are basically invisible.

The offside indicator tell tale was the first to get an LED retrofit in the form of my experimental prototype. So how does it compare to the original incandescent version?



The improvement is quite obvious I think. The use of a warm white rather than coloured LED means the colour still looks like a filtered incandescent lamp though which was always a requirement for me. With the exception of the ignition light (as it's actually part of the charging system) I'll probably set about replacing the rest of them. I'm undecided as to whether to also do the lamps which illuminate the panel, I probably will though in the interests of reducing temperatures inside the cluster and removing load from the somewhat marginal flexible PCB. Using warm white LEDs like this should retain the original colour essentially unchanged so it shouldn't be obvious that anything has changed unless you know to look for it.

While I had this apart it also gave me the chance to sort the trim around the instrument cluster which was clipped together totally wrong and was really annoying me.

Before:



Note how the trim is all bunched up in the middle.

After:



This is how it's meant to look. You can see there's now a gap between the top edge of the warning lights and the trim. It was just sitting on there before.

I'll replace the foam around the base which has dissolved at a later date. There's a similarly knackered strip internally at the top which is meant to stop light leaking out above the caution & warning panel which has also dissolved. I've got some black foam weatherstripping which will do just fine as a replacement.

The new speakers for in the front arrived early this evening.



Fitting those will probably happen tomorrow. Will look a lot less conspicuous than the bright red things which were in there before, and I trust Pioneer kit to sound decent too.

The headlamp wiper on the offside was missing 90% of the wiping edge of its blade so obviously wasn't really doing much. These short wipers are ridiculously expensive for what they are, so instead I hacked up the old windscreen wipers I took off the windscreen a week ago and used that to rebuild it.



Was stuffed as far as clearing the windscreen was concerned, will do absolutely fine for a headlamp wiper for a while though. You can see how little the old one was doing in the photo above.

A few parts have arrived from Motorserv as well.



Still astonished the brake discs & pads only came to £111, I was bracing for several times that figure.



There are four metres of fuel line in there too which will be used to replace crusty vacuum lines as they're found. It will be interesting to see if that alone revives the cruise control. That fuel filter will replace that horrible red anodised thing in the engine bay currently, and will look far less out of place.

All little things, but they all add up eventually.

The only other thing of note today was that I decided to put the Invacar on the battery charger for the afternoon. Figure with it having not been run properly in a few months it would probably benefit from it.



This has also finally been dragged off the van and has been stuffed into the garage.



It hasn't cleaned up badly really. I do need to try ringing up the manufacturer to see if they can provide me with any documentation with regards to how to drive the thing...though there are only two buttons (and one of those is "print") so it shouldn't be too difficult you'd think!

The drizzle did give me the opportunity to grab a couple of the obligatory water beading photos before we went out today, so it would be rude not to post those wouldn't it...

[xantia_v6]

The LED warning lights are certainly an improvement.

Fuel hose is not necessarily suitable as vacuum hose, as it may collapse under vacuum when hot.

[white exec]

Big improvement!
When it comes to instrument illumination with LEDs, it gets fun, because of directional considerations.
You'll likely have to revise the value of the rheostat as well, to retain proper dimming.

[Zelandeth]

This hose I've used before without trouble, it's sturdy enough that it should be okay. The flimsy rubbish in Halfords I would definitely not want to use though! It's the only option they had available though, and I'd rather keep things local if I can. If we do need to pick up some vacuum specific hose I'll just have to resort to online suppliers though.

These LEDs have essentially a 270 degree viewing angle give or take as there is no lens as such, which is why I specifically get these. I'm not really worried about the rheostat as the dash lighting is sensibly muted rather than eyeball searing. I'll give it a try, if the LEDs don't work well for the panel illumination I'll leave it standard. To be fair that works just fine on the instruments... it's just the warning lights that are way too dim.

Oh, and the heater control lighting which may as well not exist...though hopefully multiplying the amount of light getting thrown into the system by a few times will help with that.

[Zelandeth]

Out running some errands earlier and we had a good result in that this started working again.



That was a nice easy fix! Have to assume that one is another thing which was faulty primarily due to it not having been used regularly in years. Investigation of why it wasn't working was somewhere around number nine on the to do list, so nice that it's sprung back to life on its own. The system will be getting serviced in due course, but servicing is easier than restoring a system that's simply "dead."

The first of the new speakers has been installed.



The new speakers being slightly smaller has worked to my advantage in a couple of ways. For one, they look more in proportion I think. Secondly it means that the speaker surrounds no longer catch on the sill kick plate which the ones that came with the car did.

I had to glue some little wooden blocks to the inside of the door card to screw the speaker too as it was fractionally too small to get all four screws attached due to the size of the existing hole. Took all of five minutes to sort though and wasn't something I was worried about as the grills are more than big enough to hide the slightly messy edges.

While I was looking at audio I had a closer peer at the head unit in the dark with a torch to try to confirm (as I've been unable to find a decent photo of this unit) that there is evidence of the buttons being illuminated.

Using a bright light source shone onto them reveals clear portions where the text is, so there definitely should be lighting in there as I expected.





The lamps were probably killed off by the illumination line being incorrectly wired up to the permanent 12V feed for goodness only knows how long. I'll pull it apart at some point to restore functionality of the lighting.

Speaking of lighting curiousity got the better of me as lighting technology is an interest of mine, so I went digging to take a look at the light source for the fibre optics.



It's the silver and black cylinder just right of centre. So pretty easy to get at (just three screws hold the panel above it on). Pulling one of the lines and playing around even with the not particularly bright light from the torch on my keyring shows a great potential for improvement of the lighting. The bottom of the temperature control here is being lit by my torch. Top is the normal light source.



Camera has made it look way brighter than it is...but it's actually visible to the naked eye there...the lighting at the top of the dial wasn't visible above the ambient light to the naked eye. Will be nice to give that a bit of a boost as I think the visual effect looks really nice...it's just laughably dim.

One job for the weekend may be to get the front brake discs and pads changed. Are there any particular traps for new players I need to be aware of there? Hoping they're just a bolt on/off job and doesn't involve messing around with the wheel bearings...

[white exec]

Did any other cars get fibre-optic lighting? First time I've heard of it...
Lots of scope for colour games there!

[myglaren]

The Princess I had had fibre optic lighting - I still have some of the optical leads here somewhere.

[xantia_v6]

The front brakes are easy... assuming that you know that the disks are bolted to the inside of the hubs, so the hubs need to come off the stub axles to change them. And the caliper bolts have saftey wires, so have some suitable lacing wire on hand. Maybe the steering arms share one of the caliper bolts maybe some shims there, just put everything back in the same place.

[Zelandeth]

Had a run out of town today and actually had clear roads, so steady driving using cruise was the order of the day. Did this improve my economy?



Yay! Wait...it's still awful...but better. Hoping that things will improve a little bit at least after a proper service.

[white exec]

No, no. Think of it as just battery voltage . . .

[Hell Razor5543]

No, no. Think of it as just battery voltage . . .

Don't you mean output voltage from the alternator?

[Zelandeth]

Did any other cars get fibre-optic lighting? First time I've heard of it...
Lots of scope for colour games there!

Missed this question!

BMC quite enjoyed playing around with it around this time. Even the Mk II Metro got some, the legends actually on the indicator and windscreen wiper stalks being lit that way.

Other cars I know of which used fibre optics off the top of my head were...

Volvo in the 90s. Everything aside from the instruments themselves in the 440 and 480 were lit with them - including the button on the seatbelt buckles!

Fiat did the same in most of the late 80s and early 90s models.

The little light pipe legends Jag used here though do look particularly classy I think with how the text appears to "float" in a very three dimensional way. Here's everything they have used the fibres to light in the XJS.

HVAC controls:











Headlamp switch.





Plus the ignition switch, not something I recall seeing lit like this before...know a few cars where there is a light tied to the courtesy light circuit to help you find where to put the key, but don't remember seeing the positions labelled and lit other than in Jags of this vintage.

[white exec]

The 3D effect with the acrylic is quite striking. Clever, too, as the plastic will "light pipe" as well.
Some good photos, Zel.

14.4 ... I did mean on-charge system voltage, tongue-in-cheek ...