NOCO Genius charger problem


Senior Member
Mar 24, 2016

My truck and FWC Grandby have not seen much use for about a year and I try to keep the lead acid truck and single lead acid house battery charged with a NOCO Genius charger. I recently let life get in the way and learned the truck/camper batteries had discharged during a long time in the garage.

Connected the NOCO Genius and noticed a strange cyclical flicker in the camper clearance lights when charging. Lights on truck were off...and I have no clue what is going on. The next morning the NOCO had gone to some sort of failure mode and neither battery had charged.

Not sure what to do next.

David Graves
I’d start by separating the batteries & attempt to charge each by itself. Keep any that come up to charged. Should let you know where you stand.

I had a Noco genius that failed on me. I let it sit for a few months and it started working again. Then it failed again and this time for good.
If a battery is dead enough the Noco won't start charging. Like PaulT mentioned, separate the batteries and charge each individually. If that still doesn't work, put the Noco into power-supply mode and charge the battery for an hour or so. That should put enough charge into the battery that the Noco will charge in it's normal mode. The Noco only charges when it senses the presence of a 12v battery. If the battery is deeply discharged the Noco won't see a high enough voltage to start charging. The power-supply mode forces the Noco to output the 13 or so volts and that starts the battery charging.
Thanks for the comments.

As an update I disconnected the truck battery from the truck.
I charged overnight with my NOCO G7200 and the truck battery indicates fully charged.

When I connected the truck battery there is a slight spark and the camper clearance lights flash on/off briefly.

I think I need a new house battery but I am not at all sure what goes with the lights.
As with most campers, my clearance lights are grounded back to the truck itself.

I hope all the electro-wizards have fun with this...I am all ears.

Top Bottom