Greetings ....

I've been through this loop before, with instrument cluster failure - eventually curing the matter with a s/h complete cluster unit. Problem solved.

So, I'm quite familiar already with the usual problems.

This one may be different.

All the instruments in the cluster work, except the speedo itself.

When the key is put in the ignition, the needle on the speedo jumps and settles on 0mph, which suggests that power is getting there.

A message flashes up on the unit, saying that there's a "loose connection" somewhere.

I've done all the usual things like look at all the fuses (inc those under the battery cover) and jiggled all the plug-in components just in case there's a dry joint somewhere.

To complete the picture, the odomiter has also ceased to register any further mileage ...

This suggests to me, that possibly (just possibly) the problem might not be related to the speedo unit itself, but the electric sender unit somewhere in the bowels of the engine bay.

"Is there a fuse perhaps hidden somewhere I might have missed, or has a wire dropped off the speedo sender", I ask myself ?

If someone has any trhoughts on the matter (like where I might find the speedo sender), I'd be grateful to hear them !

Thank you ...

There's no speedo sensor as such. Vehicle speed is measured by the wheel speed sensors that send signals to the ABS ECU, which is connected via the CAN to the engine management ECU, body computer and speedometer cluster.

Thank you for your imput, which is appreciated.

The wheel speed sensors might be located where ??

The reason I suspect this might be a component failure/loose wire somewhere, is that the car spends its time on some pretty rough and potholed roads at times (agricultural tracks etc) .... and something might possibly have been jolted loose somewhere and I'm fishing for someone to suggest where I might look.

If not, or it proves to be a wild goose-chase - well, then I'm up for another JTD cluster !

If in the meantime, anyone has a JTD cluster, or knows where I might find one, then let me know please and I'll get in touch.

Cheese.

There's one wheel speed sensor on the hub carrier of each of the four wheels, however, if one of the sensors was at fault or disconnected, you should be getting an ABS fault code, and a warning light and/or message on the cluster.

I'd advise reading the fault codes before diagnosing by substitution.

Sorry,

I forgot to also mention that several of the warning lights also lit up at the same time, including the ABS light ....

Is is possible to paste a schematic, showing me where the hub carrier sensors might be located. It would be appreciated.

I suspect, it will be the front rather than the rear units affected, as the front suspension takes a regular amount of real abuse.

I've had mine apart and fitted a new strut on the front a few weeks ago, and a new lower wishbone. I didn't see anything then on the hub that looked like a speed sensor .... and as I recall the only wiring I recall seeing, was the brake pad wear indicators .... (I've replaced those too, some time ago). Perhaps worth jacking the thing up and having a look, if I knew where to ..... can you help ?

I haven't discounted the notion that the cluster has died (again), but am examining other possibilities as well, before lashing out yet more cash !!

The front sensors would have stayed on the hub carrier while you replaced the strut and wishbone.

Diagram from eLEARN below for the front sensors. The connectors for them are under the bonnet by the suspension turrets I believe. They are long black cylindrical conectors.
.

Excellent,

Most helpful.

Appreciation given for your time ....

I'll print out and investigate ....

Thank you

Cheese

An update, in case anyone is interested - and an unusual solution !

Speedo sensors are working just fine, it's the intrument cluster itself that has failed.

Having replaced it once, with second-hand ones being rarer then rocking-horse poo (and expensive too) I decided on another solution.

So I went out and bought a basic Garmin40 satnav, that has a speedo facility built into it - a large circular affair with a very clear digital readout.

Looking at the MOT regs on the VOSA website, it's probably not a MOT fail to use a satnav as a speedo - see link http://www.motinfo.gov.uk/htdocs/m4s06000701.htm and in any-case it gets me out of immediate trouble for the moment !

Stilo JTD cluster £30 at the moment.
http://www.ebay.co.uk/itm/390547723226