On Board Computer Not Sat Nav Version
 

How do I reset My Average Fuel Consumption??

I have tried to hold the button in but it does not reset and Goes to PROG and changes across to the Radio And displays different things ie.. Distance Stopwatch, Range, etc I can't get my head around it

If I understand what you're asking, you're most of the way there.

When it goes across to the radio buttons, notice which button has the asterisk adjacent to the title. Select CONS1 or 2, and when the asterisk is next to one or the other, the number should be displayed on the upper line of the radio screen. Press the SET button, which is further along on the list of keys, and it should zero-out that setting. Do it again for the other one. (I'm doing this in my head, so may not have all the steps exactly right, but it seems like that's how I do it.)

Hope this helps,
Dave