I have a FCV-600l I have 12 volts to the load side of the 3amp fuse yet I can not get the unit to power up. What should I look for? Is there some sort of "card" that needs to be installe din the bottom of the unit. Please help I just purchaced this boat and need to go fishing
The FCV-600L doesn't have charting capabilities thus doesn't use a chart card. Even if it was a chart plotter the lack of a chart card won't prevent a unit from powering up. The true test in checking voltage is to measure it on the back of the power connector as you are trying to power up the sounder, but the FCV-600L uses a molded plug so that is not an option for you. So making sure there is no corrosion on the power plug pins and connector will be the best you can do. If this looks OK and it still won't power up, I would take into a Furuno dealer to have them bench test it.

Snips, thanks for the info i will try to find the dealer close to norther va. Chris