Power for New Frig Exhaust Fan Install

rcarlson1957

Trying to install a 12v dual exhaust fan in frig exhaust vent. Everything mounted ok and works fine when testing with an external 12v battery but when hook up to 12v on top of frig it's a no go. I have a 2018 T@B 320S with the Norcold N.180 3-way frig. Anyone done something similar and if so where did you pick up power? Here's a pic of power bus bar on top of frig under stove. White and blue wires at 3&4 are 12v input, and gray/yellow and red are 12v output to frig. Maybe I'm having a brain sprain but picking up 12v at white blue wires from battery on multimeter when disconnected but get 2v when hook power wires to fan controller directly to them. Also get 12v at gray/yellow and red pins but when hook up to power wires to controller drops to 2v again. Probably something simple but just not getting it. Any idea?

Grumpy_G

Sounds like you have a very low resistance/almost short connection to *chassis* ground somewhere. Use the ohm meter setting between the power feed for the new fans and chassis ground (could even be at pin 3 of the junction block). 
The reason it works with the external battery is that this battery does not connect to the chassis so it doesn't complete the low resistance circuit. 

Bayliss

@rcarlson1957, I sent you a private message with several discussion thread links re similar installations.  Hopefully, you will find some helpful info among those posts.

rcuomo

 Here you go: https://tab-rv.vanillacommunity.com/discussion/7535/norcold-3-way-auxiliary-fan-kit-my-install-in-2018-t-b-320s/p1

rcarlson1957

@Grumpy_G, @Bayliss, @rcuomo. Success! Sometimes it's the simplest things. My converter panel isn't marked. Was working on another issue and had wrong fused pulled after verifying with multimeter. Converter panel is definitely marked now. Finished product. Thanks, everyone!

rcarlson1957