Speedometer out of action.

[DougWomble]

Problem as in the title.

For the last couple of weeks, at 30-40mph the needle would rapidly oscillate, with an audible rattle. Faster or slower, it would behave as normal.

Now (three days after its MOT) it's stuck at zero and refuses to budge.

Before I go taking the wheel off / dismantling everything, does anyone have a view on whether it's a loose connection or it's a broken cable, so I can set aside time over the weekend accordingly.

Advice appreciated - TIA.

[ianaudia4]

Before you go taking the clocks out take a look at the gearbox end, the drive at that end may have broken. They are (or were a couple of years back) available from the dealers for about a fiver. I believe there are two types, one for injection and one for carbed cars.

[mark1gls]

Usually if they start to jump about and make a noise it means they are about to break which might of happened to yours, but as ianaudia4 says and check the end by the gearbox first but be careful removing it from the gearbox as the plastic end can fall off into the gearbox and that's not an easy job getting it out!
There is different coloured ends depending on how many teeth it has so go for the same colour if it's worn out.
If it's OK then next job is remove the instruments and drive the car to see if the end of the speedo cable turns, you dont need to move much as it's easy to see it spinning around. If it's working OK then it might off come lose from the back of the instruments and push it back on and check the speedo works before fixing every thing back in.

[DougWomble]

Thank you for the replies.

I've had a look behind the instruments - the end of the speedo cable doesn't turn, plus the connection wasn't loose, so the problem doesn't seem to be at that end.

When it comes to looking at the gearbox end, what should I be looking to do? e.g. loosen the hex nut then unscrew the end of the cable or pop it out?



More importantly, how do I ensure I don't end up losing the plastic end into the gearbox? This is my biggest worry to be honest, and what's stopped me from taking it apart so far. I've googled it, and doing just that is actually quite common, but no-one really says what precautions you should take.

Needless to say, I appreciate the help as always!

[ianaudia4]

Undo the 10mm nut and pull the cable out, you will see if the drive has broken.

[mark1gls]

There should be a little C clip holding the drive gear onto the cable so it should not fall off but it does not always hold if the drive is knocked pulling it out so as ianaudia4 says undo the small oily bolt in the picture and try to pull the speedo cable out keeping it as straight as possible so the drive does not hit the sides and keep your fingers crossed.