intermittent rev counter/horn fail

[Kes]

Can anyone throw any light on this problem? Occasionally (although becoming more frequent lately) the rev counter will drop back to zero whilst I'm driving. It seems that at the same time the horn stops working. Both usually start working again after a few minutes....
Any idea where I might start looking for the problem?
Thanks,
Kes

[christopher storey]

Sounds like a bad earth. The Electronic tacho on an S2 usually needs the case to be earthed as the readout ( but not the sensing which depends on the inductance from the white loop wire ) depends on the tacho having a viable 12 volt supply via its green wire and a satisfactory earthing of the case. The horn also is requires a good earth to work properly and if the two are ceasing to work simultaneously it is likely that some common earth is being interrupted

[Keith in Norfolk]

Check the fuse holder as well as the fuse , mine had melted making it a bad connection and causing the same
faults you have described.

[mgcjag]

Come on Keith keep up ...he asked the question 4 years ago

[288gto]

In fairness Steve, he never came back on to say thanks I've fixed it. He might still be stuck crying in his garage after four years surrounded by a dissassembled E type that started off as a simple electrical fault.

Simon

[mark10337]

like the rest of us you mean? Come on Simon, it's time for an update on your rebuild...