Race Technology have tested the unit and they say that nothing is wrong with it, so it must be something to do with the wiring. Even though it;s not their fault, they are being most helpful and getting it solved which is excellent of them.

I have tried earthing the DASH2 directly on the battery but it changed nothing. Between us we're still convinced it''s an earthing issue though.

I have tried disconnecting all sensors and testing each one in isolation and they all vary depending on if the lights or engine are on or off.

I have read a post from another user who has not used the tacho feed to power and earth the DASH2 though - he has run hi sown connections and says it's fine. I am going to try this and see what happens...