In addition to the informaton that you already received, here is a Q&A I wrote back in 1998 that might help.
Question:I have some minor repairs that need to be done.Can I use an unlicensed handym ... read more
If it's solid red it might be indicating a tripped GFCI, if it's flashing it might be defective. When I say might it's because not all GFCI-s have the same type of light or color. Some are lit when o ... read more