The display seems to be showing only mpg at present where it jumps from 40mpg to 117 mpg in an instant - cant seem to get it to change to the other options ie average mpg since last reset - miles left in tank etc etc. any ideas.

 

Do you mean the buttons on the end of the stalk have stopped working?

Problem solved - senile dementia being the problem ,after doing whats required hundreds of times i forgot and kept pressing the zero button on underside of stalk expecting it to scroll through the different options .

nice easy fix then!