Panel Lights Breaker is blowing

The "panel lights" switch on my console light up the switches (nav/anc, cockpit lights, engine room lights, wiper, bilge, horn) and the instrument gauges. When I hit the switch to light them all up, the background of the switches light up, the gauges light up very very dim, and then the breaker pops...

How would I fix this and where would I start? I'm sure there are a number of reasons it keeps popping, but I want to know where to go. I haven't installed any new electronics and I haven't touched the wiring.

Happy Father's Day to all the dad's out there...

Thanks!

Re: Panel Lights Breaker is blowing

One way to attack this without using a meter is a divide and conquer theory. Look for places to disconnect various parts of you meters and gauges. Recheck again, when you remove something that no longer blows the fuse, you should have the offending line disconnected. Keep thinking with the water pipe theory. With the water flow being your current path. When you shut off the bad path the current draw will be reduced.

Re: Panel Lights Breaker is blowing

Take a close look at your gauge wiring, i've seen more than one set of melted wires this spring. If your gauges are dimming I would bet thats the circuit you need to check closely, you could have a ground touching a 12v post on one of the gauges or something got hot and melted a ground/hot wire together. If you had fuses instead of breakers they would be instantly popping and probably wouldn't light at all!

Re: Panel Lights Breaker is blowing

alright everybody keep the help coming..

worked on the instruments and switches earlier today... i disconnected each instrument and switch one at a time, and hit the panel lights switch, and every time it popped... don't know where to go from here.

keep in mind, the actual instrument gauges work, its just the lighting behind every one. the switch lights come on perfectly, and the instrument gauge lights come on very dim, for 1 second, then the breaker pops...

know where i can go from here?

Re: Panel Lights Breaker is blowing

I take it you have a separate "Panel Light" switch -- correct? If so it is that circuit that is the issue. Instead of disconnecting the gauge, disconnect the light at each gauge (remove the bulb as well) and try. Since the breaker blows in one second, that says "direct short" exists. The panel lights are typically wired with a blue wire. There are two theories on troubleshooting. 1) Start at the source (the switch) and work downstream. or 2) Start at the end (last bulb) and work upstream toward the switch. To eliminate the switch as a problem disconnect the circuit at the switch and turn it on. If the breaker blows you need a new switch. If not, connect the wire and go to the next junction.

Re: Panel Lights Breaker is blowing

I also subscribe to the divide and conquer theory. If the circuit is fairly easy to identify, disconnect at the half way point and then you will know which half to start on. If you want, you can then start in the half way point of the half that fails and now you have the circuit split into fourths.

Re: Panel Lights Breaker is blowing

correct, i have a separate panel lights switch for the gauges... every gauge has a yellow and purple wire, then pretty much each gauge has a 3rd wire that is color coded for each gauge....

how do i check the circuit, or split the circuit in half and figure out where to start?? i guess i'm confused from there...

Re: Panel Lights Breaker is blowing

The simplest thing to do at this point might be to just unhook all the wires from each gauge and test the circuit again. A quick snap shot from a digital camera can make hooking things back up easier. If you have a meter you can test without using up fuses.

Re: Panel Lights Breaker is blowing

Here is a very generic console wiring diagram.



Pay no attention to all the other stuff but concentrate on the instrument lights. You will notice that the blue wire in the diagram jumps from the light in one gauge to the light on the next and then the next. In your case the origin of this blue wire is Your Panel Light switch rather than the NAV/ANCHOR switch shown in the diagram. Simply disconnect the wire from the gauge at the end of the line, middle of the line, beginning of the line, or at the switch and work in either direction. Disconnecting the wire at the switch obviously removes the entire circuit from the switch so if flipping the switch pops the breaker, you know the problem is not in the light circuit itself but rather in the switch.