Clean It Time

Probobly need a new drive cable which is not that hard to fit.
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It’s not an easy job. You have to disconnect the speedo cable art the back of the speedometer., and at the other end of the cable, you have to disconnect it from the gearbox. You then have to connect your new cable at the gear box and route the cable exactly as the old one was. then connect the other end of the cable to the back of the speedometer. Not an easy job perhaps you should let a garage do it for you.
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What year is it? It may be covered under warranty. It may be the speedometer cable was unhooked or it needs a new cable.
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I thought these has electric speedos, sender unit on gearbox and electronics in the speedo, if so try a sender first, none of it is really repairable it will be a hideously expensive sender and then a speedo head before you realise Ratty your pet mouse has eaten through the wiring.
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