ORIGINAL: Kevin Welch
Hi there slim,
I must admit to having similar concerns when I first got my car ( only reading 3/4 full and warning light not coming on ). A simple way to alay your fears is to lift the " boot " carpet then remove the large black bung in the floor above the fuel tank, this gives access to the fuel level sender unit etc. Remove the wiring plug ( three pin ) and with the ignition on connect between the earth pin ( brown ) and the other two pins in turn. I cant remember which pin is which but one will show the fuel gauge as reading full and the other will light the warning light, if it doesnt light then suspect a faulty bulb. If the gauge still reads 3/4 full then the needle can be repositioned on its shaft to read full. The warning light is dependant on the amount of fuel in the tank ( supposed to be 13 Litres ) and not on the needle position before it comes on.
Lots of words but only takes a few minutes to check.
Hope it helps.