Keystone RV Forums - View Single Post

smiller · 05-09-2012, 05:36 PM

You probably have some electronic device hung on that 5-amp circuit that may have been damaged by the reverse polarity and now looks like a short. For instance many electronic devices have a diode across the power supply input so that if reverse-polarity power is applied the diode will conduct and blow the fuse before more damage can be done... trouble is that sometimes the diode doesn't like all that current and shorts permanently. Anyone who repairs electronic devices has seen this many times.

Anyway, you need to disconnect devices on that 5-amp circuit one by one and find out where the short is. If you have a multimeter you can use that instead of going through a bunch of fuses.

05-09-2012, 05:36 PM	#2
smiller Senior Member Join Date: May 2011 Location: Full-timing Posts: 447	You probably have some electronic device hung on that 5-amp circuit that may have been damaged by the reverse polarity and now looks like a short. For instance many electronic devices have a diode across the power supply input so that if reverse-polarity power is applied the diode will conduct and blow the fuse before more damage can be done... trouble is that sometimes the diode doesn't like all that current and shorts permanently. Anyone who repairs electronic devices has seen this many times. Anyway, you need to disconnect devices on that 5-amp circuit one by one and find out where the short is. If you have a multimeter you can use that instead of going through a bunch of fuses.