electronics not working

[Rzide]

So, after tracing wires and trying to find all fuses i'm stumped. the only electronic on my dash, as far as navigation and communication that works is my gps unit where you enter the coordinates.

The other units will not turn on like my chart plotter, radar, and such. Its all raytheon, r41xx, etc, that I believe came stock on my boat. After trying to figure it out, I found that the fuse bus, that's directly behind the fuse panel below the steering wheel is only getting 2-3 volts. This is at the power wire feeding the bus.

However, the power at the units appears to be at 12 volts. All fuses are good that I can see, however I cannot see if there is a fuse in-line, feeding the electronic nav fuse bus. I have not torn all the wiring apart in hopes that this is a simple fix for someone who knows what is going on, I'm no electrician. I would just guess the units are bad, but, again hoping for an easy fix.

Any help would be appreciated.

 

[dtfeld]

trying to figure this one out. Where r u measuring voltage across..specifically. Not possible to have 3 volts upstream of 12 volts...

possible a bad ground wire...

 

[Rzide]

trying to figure this one out. Where r u measuring voltage across..specifically. Not possible to have 3 volts upstream of 12 volts...

possible a bad ground wire...

It's hard for me to describe because I don't know what I'm talking about and because I don't know for sure how it's wired.

The way I believe it goes is a main power line to the fuse bus , the bus then sends individual fused power to each monitor/system?

I'm reading 3 volts at the main power wire connection that goes into the fuse bus. But I'm getting 12 volts at each monitor for the systems. I don't understand how I'm getting those readings either if my understanding of how it's wired is correct..... I'm at a loss.

 

[dtfeld]

hard to tell... usually there are 2 possibilities.

1...Main power line—>>fuse panel —>>panel switch —>> component

2...Main power line—>>fuse panel —>> —>> component