Speedo not working

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guss300
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Post Sat Oct 05, 2019 11:32 am

Hi my speedo is not working and the miles dont go up. Also the economy thing is not working. I have taken the clocks out and there are three wires that I dint know where they go see pic below and any help will be appreciated
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Cloggy Saint
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Post Sat Oct 05, 2019 11:44 am

Those wires are nothing to do with the speedo', possibly left over from an alarm or immobiliser? Have you checked the plug and wiring on the diff? This is the usual culprit for a failed speedo.
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guss300
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Post Sat Oct 05, 2019 11:46 am

No I haven't will.do that
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guss300
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Post Sat Oct 05, 2019 11:47 am

When I put my foot down the economy gauge sometimes works but not the speedo
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guss300
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Post Sat Oct 05, 2019 11:53 am

The green wire was connected to the green plug somewhere on back of cluster but came out and dont know where it goes
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Brianmoooore
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Post Sat Oct 05, 2019 9:13 pm

Cloggy Saint wrote:
Sat Oct 05, 2019 11:44 am
Have you checked the plug and wiring on the diff? This is the usual culprit for a failed speedo.
As above!

Most pins on the green plug at the back of the cluster are a speed signal out of the instrument cluster, and feeds various optional extras, such as cruise control or speed controlled radio volume.
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Brianmoooore
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Post Sat Oct 05, 2019 9:38 pm

Wires to the speedo sensor in the diff are pin 8 (brown wire) and pin 12 (brown/red) of the white instrument cluster plug. The speedo. sensor itself is a simple on/off switch that operates several times per turn of the rear wheels.