wiring diagram

[handymanat39]

Hi all
My first post, I live in the Uk and have just bought a carver montego 24ft, this week she refused to start just clicking, I have a fully charged battery checked the earth on the engine (volvo penta aq171c). Also the rest of the electrics have now packed up, test at the fuse box shows 5volts.
Any known issues or where it could be getting lost ie dirty connections?
Many thanks.
Andy

 

[Silvertip]

The negative (earth) is only one side of an electrical circuit. The positive terminal at the battery and at the starter solenoid are equally important. Looking at them is not a valid check. The cable should be disconnected, made shiny clean and then securely connected on both ends. There may be a second positive and negative cable at the battery (approximately 10 gauge) that powers the fuse panel. A problem in that circuit would kill all "house" circuits. There is typically a circuit breaker or fuse in the positive house circuit cable within a few inches of the battery. But if there is only 5 volts at the fuse panel then corroded battery connections are the likely culprits.