Fascinated by the question I searched around - "Dash" problems seem to be quite common on several Reanult models - People complain about the total mileage jumping erratically upwards to silly numbers. Others report a replacement cost of £500-£600. Many talk of poor response from Renault. One or two have fixed it themselves by checking for and repairing dry joints on the circuit board particularly around the voltage regulator area.
A commercial organisation is offering repairs for £195 with a turnround tme of 48 hours...
http://www.carclinicmagazine.com/renault_megane_scenic_instrume.html
The volume of web traffic on these Renault Dash issues is quite large - Renault claim there is no "known problem" which is interesting - once they admit that there is a Known Problem (i.e. They know about it, its cause and a solution to it) they go some way to admitting liability. My guess (and it is only a guess) is that the manufacturing process had poor quality control and vibration over time is making dry soldered joints show up.
I am glad that I don't have a renault...
Good luck...
Peccavi
May 2009
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