Question about troubleshooting electronics on 19' CC

Good Morning,
Haven't been hear in a while... So boat is running good, but having issue with electronics and need to find a good starting point.

I have a 19' cc Sea pro. There are about five switches that control bilge, live well, boat lights, tach lights that are not working. They all previously were working. There are lights on the switches too that don't work. The speedometer, rpms, fuel guage are all working.

How should I go about troubleshooting this? Since none of them are working it has to be something connecting all of them.

They are were working a few weeks ago.

thanks in advance.

Re: Question about troubleshooting electronics on 19' CC

Since all of the switches are fed from a common source of +12 volts, an interruption of that circuit would also cause the same symptom. Since the instrument lights are not working, and they generally have the same ground as the instrument itself -- which do work, a ground problem is not likely. A quick check for voltage on the LINE (the input side) of any of the switches would show +12 volts or not. If You have +12 volts on each switch then individual ground issues are the culprit. Again, since these non-functional devices are grounded in various places, it is highly unlikely all of them are open.

Re: Question about troubleshooting electronics on 19' CC

Great thanks. Yes none off the switches are working or lighting up that is what makes me think it is one problem connecting them all. So since the speedometer and fuel guages are working but the lights for those tachs aren't, could it be a fuse? Or does that rule it out.

Would you start by taking one switch out and checking with a volt meter? If I have power then maybe run a temp ground? Don't know too much about troubleshooting electrical so go easy.

I mentioned fuse, because I notice on the battery, i have the main cables, but I also have a smaller guage that the power (red) has a fuse. I assumed that was ok, because boat starts with key and as i mentioned, the tachs work.

thanks guys for the opinions and advice!

Re: Question about troubleshooting electronics on 19' CC

1) You don't need to remove switches to check for power. Get down and under with a voltmeter or test light.
2) A boat has two electrical systems. A) the engine system feeds the ignition switch which powers the gauges and the engine circuits. B) The boat electrical system is a red and black (#8 or 10 gauge) pair of wires that feeds the helm.
3) there should be a fuse or circuit breaker back near the positive terminal of the battery. If it is blown or the breaker is popped, anything powered from that circuit will not work. Check it.
4) the instrument lights may be powered from the boat harness via the NAV/ANC switch, or they may be powered any time the key is on. If they are powered from the NAV/ANC switch and they work, then the boat harness is not the problem. If they are powered from the ignition switch and they work then the boat harness may indeed be the problem.

Lastly -- that fuse you saw in the smaller pair of wires is what I just described and has absolutely nothing to do with the engine. It feeds the helm and the accessories -- not the engine. The big battery cables feed the engine circuits. Check that fuse and your stuff will likely come alive. But then figure out WHY it popped or it will likely pop again.

Re: Question about troubleshooting electronics on 19' CC

I agree with the above post. That fuse near the battery is most likely the problem. That wire should be for your accessories and is a completely different circuit than anything engine related.