12 V panel problems

[Tmacmi]

What’s wrong with my electrical panel?

1) the instrument switch will not turn off

2) the battery condition meter shows voltage when I switch up and down even though one battery is removed.

The only thing I’ve done is to remove some electrical tape from wires that serve the VHF radio and an old car radio that are connected to the instrument switch.

[OldGreyB]

Most car radios have 3 power connections. Red 12V+ , Black 12V- and a third wire, Yellow 12V+. The Yellow is usually connected to a non switched 12V+ supply, via its own small inline fuse. This power is utilsed by the radio to keep the Station settings memory active.

Perhaps your action of " The only thing I’ve done is to remove some electrical tape from wires that serve the VHF radio and an old car radio that are connected to the instrument switch. " has now inadvertently connected the Yellow 12V+ to the Red 12V+ from the switched side ( LED Side) of the Instrument breaker, thus powering the LED and anything downstream of the "off" breaker.


The PO probably had a reason for the electrical tape.

Check all the wiring insulation is complete and no wires are crossing and touching copper to copper. Investigate and redo damaged wiring with heat shrink as your insulation . Also check right at the plastic connector bases, as just your fiddling, may have shorted out wires there.

[Tmacmi]

Originally Posted by OldGreyB

Most car radios have 3 power connections. Red 12V+ , Black 12V- and a third wire, Yellow 12V+. The Yellow is usually connected to a non switched 12V+ supply, via its own small inline fuse. This power is utilsed by the radio to keep the Station settings memory active.

Perhaps your action of " The only thing I’ve done is to remove some electrical tape from wires that serve the VHF radio and an old car radio that are connected to the instrument switch. " has now inadvertently connected the Yellow 12V+ to the Red 12V+ from the switched side ( LED Side) of the Instrument breaker, thus powering the LED and anything downstream of the "off" breaker.


The PO probably had a reason for the electrical tape.

Check all the wiring insulation is complete and no wires are crossing and touching copper to copper. Investigate and redo damaged wiring with heat shrink as your insulation . Also check right at the plastic connector bases, as just your fiddling, may have shorted out wires there.

Thanks for taking the time. I know the open ends of the red and yellow aren't touching. See the photo and info embedded. The only thing I did was unwrap the wires shown.

[Kelkara]

some thoughts ...

1) If the instrument circuit can't be turned off then either a) the breaker has failed to always be closed, or b) some other 12V+ live wire has shorted against the switched side of the instrument circuit.

so ... a) test the switching function of the breaker, and if that's ok, b) turn off all your other circuits one by one, including the yellow wire, until everything is turned off, to see when the light goes out.

2) if the meter is reading voltage whichever position the switch is in then either a) the switch has stuck in one position, or b) something is connecting the two battery circuits together ... do you have a 1-2-both battery selector switch that is set to both?