Hi Guys

The Weather turned out nice after all, so decided to go for a drive after 17 years of restoration.

Which involved going over the Melton Railway Crossing, that Greg and Leo will be familiar with.

Its on a very dangerous bend, where you can often come across a Truck going round this tight corner, so you really need to be doing less than 20/25 mph.

As last year I remember a Truck coming round this bend, well over the center line in the middle of the road

Where I had to drive up on the verge to avoid his Trailer cutting my Car in half.

So after that scare I had last year I was taking it very Slowly but as I went over the Railway Lines, the Speedometer just cut out

Where the Speedometer Needle dropped right back to Zero in the Middle of this bend.

While I'm not too familiar with the way that these things work, I've got a feeling something sends a Signal to something else.

But once I was over the Railway Lines, it started working normally again.

Could the juddering going over the Railway Lines have caused this?

Just to be sure it wasn't a fluke, I turned round and then retraced my Steps.

But when I went over the Railway Crossing for the Second Time all was ok.

Any ideas as to what could have made the Speedo suddenly cut out and the needle drop to Zero, without any Warning.?

Could the Juddering over the Railway Lines have done that?

 

Possibly a loose plug, bad contact, torn cable... Loads of things it could be. Just keep an eye on it...

 

Yep as Damien said I would suspect a bad connection first.

Could be in the instrument cluster, I would look at this last as it requires removing the cluster.

CP7 is under the centre console, there are connections there that go from the speed unit in the boot to the cluster TC and CC.

The speed interface is under the LHS buttress inside the boot there are a couple of plugs there as well. You'll know it, it has Speed Interface written on it.

 

Hi Warrjon@Daim

Cheers Guys!

Not knowing anything about Auto Electrics, please could you tell me more about CP7 as I have no idea at all what that is.

Would it be a Fuse of some kind?

When you say remove the Center Console, do you mean the Glove Box or the Ski Slope? or maybe even both?

 

it's a connector as listed in the relevant jag electrical guide OB. You will find all the connectors and where to find them and pin allocation in the guide at fig 1.1 harness layout connector locations.

 

Hi Baxtor

Cheers!

But I don't even have a Haynes Manual and am absolutely hopeless at reading electrical guides but as you may already know.

Right now I've got an even bigger problem on my hands with a Seized Fan Clutch.

The XJS Saga never seems to end, especially as I've only just got her back on the road.

If I'd paid a Shop to do what I've done, it would cost me more than the Car.

 

Ah that's the pleasure of owning an old car...................

Electrical guides here

JagRepair.com - Jaguar Repair Information Resource

Buy a ROM on CD they are worth it.

 

Hi Warrjon

Cheers!

Many Thanks for that.

When the Speedometer Needle dropped to Zero, I thought that the Engine had cut out!

Which is not ideal when you're trying to drive across a Railway Line.

In case there is a Train Coming and they put the Barriers down!

That was a heart stopping moment, as I couldn't tell if the Engine was running or not

And as I was going so Slowly, I didn't think that I had enough forward momentum to be able to get round this tight and dangerous bend

In the event the Engine had cut out, which is hard to tell in those few Seconds.

 

I fixed that problem with an exhaust, no way my engine could cut without noticing..........lol

 

Hi Warrjon

My Engine is so quiet that you can hardly hear it run

 

Hi Orangeblossom,


Glad you are enjoying the car after all that hard work.


I occasionally have a similar issue with my car after it has been left standing for an extended period in the garage. I think it is just an imperfect electrical connection somewhere in the system and the car is normally fine once driven for a while.


I would just drive the car and only worry if it becomes a commonplace occurrence.


Cheers,


LeeP

 

Hi Leep

I think you may mean 'WAS' enjoying the Car, as its in my Shop in pieces at the moment.

We went out for a Trip and the Fan Clutch seized up, so I've had to pull it all apart again as I need a New Fan Clutch and probably a New Fan.

Details of the Saga on my 'Cherry Blossom Restoration ' Thread

And its doing my head in

 

If it was a one-time only thing, I wouldn't worry too much. My speedo sometimes dances around when the headlights are on - bad earth behind the console, probably. But it only does it sometimes, and I seldom actually need to know how fast I am going (the only real issue would be doing 60 in a 40 zone and not realizing it when the cops flag you down).

 

Hi Someday

That's one of the reasons why I needed working, as up in my neck of the woods there are constantly changing speed limits.

Which in the main are very badly sign posted, so you've got to be vigilant all the time as they are quite often obscured by bushes and can be hard to see.

 

And I bet the cops just love to grab people there.... Presumably there isn't enough traffic to just go with the flow. I have a drive recorder (dashcam, though it's not on the dash), and that gives my speed as well. Interestingly, we discovered my speedo reads about 5 kph faster at about 100 kph than the dashcam reading. Or the dashcam reading is low by 5 kph. One or the other....

 

Here I wouldn't even bother to worry about the speed limits. The fine are hilariously cheap... 20 kph too fast in a marked village: EUR 25. 30 kph outside a marked village: EUR 40. Autobahn 30 too fast? EUR 40. They don't even fine you if you are 10 kph too fast anyhow...

I rarely go the speed limits here... Just not worth it

 

I am packing my bags to move to Bremen as I write this.
I was caught doing 67 in a 40 zone, and the fine was about 140 euros.
Actually, it's not the fine that's the problem, or even the loss of the "gold" licence (I think it's a 5 or 10% discount on insurance), but the fact that next time I need to renew my licence, I'll have to sit through the 2-hour lecture on Safe Driving Bull rather than the 30 minute one....

 

Lecture? Ouch! You get points here but everyone laughs at them. Heck, ypu can be going 20 too fast with the Police behind ypu and they don't care. As long as traffic flows. At night they are more strict though... At least in cities. Where I live NOBODY is there to complain

 

Definitely packing my bags then.... Does an XJS fit as carry-on, or should I check it?

The funny thing was, I drove my MR2 turbo for seven years without a single ticket, and in just a few months with the Jag I get nabbed. There's specific places the cops like to hang out, it seems - and you just gotta know them I guess....

 

Is it really that simple, or merely naïve me.


Just check the tach !


Carl