Anyone else had this problem or can suggest other things to check?
My battery is now fully charged and working again, but since it was flat and I had to jump start the car the other day, the fuel gauge display is now flashing 18.8 gallons all the time, so I've no idea how much fuel I have!
I've done the usual reset thing - disconnect the battery and press the computer reset button for 10 seconds then reconnect the battery - but it doesn't fix it. The average mpg, speed and distance travelled displays are working, so according to the workshop manual, this indicates the flow meter is ok. But if the fuel gauge and distance remaining start flashing after 2 minutes - this indicates a breakdown of the fuel gauge, which is exactly what happens. Maybe I need a new fuel gauge/sender unit, just seems odd that it started after the battery was flat. Thought it was just typical GTA electrics going a bit haywire because the battery had been flat and it would fix itself, but it's not happening!
I've checked the connection to the fuel tank, and battery earth and the battery is now fully charged. Anything else to check?