300 tdi speedo inop

Hi everyone sorry about the lack of catchy nick name. I have had this problem with the land rover for a few months now. The speedo dropped to '0' every now and then and then eventually stopped working altogether apart from on a long journey when it will suddenly start working again for a few minutes. The first thing I did was to replace the speedo sensor. It worked for the first few minutes and then stopped again. I got a wiring diag and checked the wiring-ok. Then I bought an instrument panel with about the right mileage-none of this worked. I am imagining that this could be a common fault with the instrument panel at this sort of mileage? The mileage is 135k. I would be most gratefull if anyone could give me any info.
Cheers Mat.

Hi Mat

Sounds more like the cable is not engaged in the drive properly.

And as for the catchy nick name its either that what others call ya or yer names already bin used so fink of sumthin else

No cable for this vehicle. Its electronic. Thanks for yor help anyway.