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Do not connect the white and green wires together, you are joining fuse 1 and 2 together. Again I will tell you, no wires go to the terminal 31b this is just an earth terminal, not needed as the speedo case earths when fitted to the dash.

Looking at the wires, yes they have certainly been cooked, probably the result of very bad wiring as a fuse should have blown before the wires got so burnt.

Test to see if there is 12v on the green also the white wire, 12v on both I suspect. If there is 12v on either wire then connect that to the "+" terminal on the speedo.

Your serial no. car, in my view, should not have the green wire from the instrument panel, just the white to the "+" terminal, do all the gauges work correctly?

"+" terminal single white
"2" terminal double black
"A" double red/green
"31b" no connection at all.

That is how your car, with your serial no., should be wired.
 

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Silver Wraith ll
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Discussion Starter · #24 ·
Hi Jake,
Thank you for your reply.
Only the green wire have 12volts. It's the feed for the speedometer.
The white wire it's a short wire. For more, he was connected into the pumps relay.
But I don't remember where...
Like you see in one of my picture, the green (only one, that's no strange?) is the feed, the 2 black wires are connected on 2, and two Red/Green wires are connected on A.
So why I have only one Green wire?
And why the white short wire was connected somewhere in my speedometer?

All the rest works in my car. Just the cruise control which is completely deleted...
 

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Right, with only the green wire having 12v, connect that to "+" terminal.

The white wire is surplus to requirements and need not be used. If the speedometer works, it would be best to remove it altogether at the petrol pump relay.

Either the green or white wires go to the "+" terminal, not both, in your case the green with 12v. Forget the white wire for now.

There is only a single green wire which comes from the instrument cluster, as the speedometer is the last in the line for that particular circuit.

It is odd that you have both green and white wires behind the speedo, I would have thought either one or the other would be there, but not both.

As a footnote, the white wire may only become live with the engine running and the oil pressure switching the fuel pump on.

Jake
 

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You will find in many cases, especially with Crewe, it was easier and more efficient to add a wire and cap it off, rather than not have it there at all. I see this frequently, especially on my 1980 SWII with fuel injection.
 

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75 Silver Shadow, 90 Turbo R
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if your speedometer works, but the odometer and trip dont, open it up youll find a broken gear, typical of these. you can buy a new gear online
 

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As you have said, looks like the wiring colours changed for the American market as there is no "white cable" anywhere near the speedometer on my British market cars.

The wiring diagrams show that the "white cable" replaces the green wire not the red/green wire. The red/green goes to the speed generator and speed control.
The white wire comes from the petrol pump relay on American market cars, which in turn is fed by fuse 2 on the fuse board.

The wiring diagrams I am looking at were printed in May 1980.

If that is no help, look at early SZ model cars as the Spirits were a continuation of the Shadow 11.

Jake.
Well said Jake,I know that any information is good but sometimes it gives you a bigger problem.If a person that puts up advice and explains why they came to a answer to the problem then it’s a lot better.I myself have been desperate and would try anything and ended up with more problems,Keep up the good work lads it’s always good for the group.
 

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75 Silver Shadow, 90 Turbo R
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link is posted, it seems all the broken ones ive seen have been red, but these are all usa cars, idk. gotta open and look
 

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Silver Wraith ll
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Discussion Starter · #32 ·
Thanks a lot at everyone,
I will open the speedometer, I'll take pictures and show you here ;-)
 

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This occurence is known to happen suddenly when the car is in motion and the gears mesh. Best practice is to set before you go.
 

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I wanted to write "Find a engineering student to design and print with 3D printer a new gear. It should take around one hour of work", but I see that it is possible, that replacement gears are already available at ebay ;)
 
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