Thank you very much for the responses.
The battery is only a couple of years old and no problem turning over from cold so don't believe the battery to be faulty.
Stixy, I assume you mean the button on the dash is shorting to earth? Do you know if this is a separate switch that can be ordered or is it part of a bigger piece of the dash. I not had the dash apart so am a little concerned that the switch should suddenly decide to short to earth, also it it was doing this would it then not work normally during driving if it was shorted to earth, would it not stick on 0.0 miles?
sorry for the dumb questions just trying to understand a little more before I go delving into the dash's internals.
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