Battery dies quickly while charging

[Torchic]

So I'm having electrical issues. 1 problem I cant seem to find any Info is why my pop up drains my battery if I try to charge it. If unplug the 120v shore power my pop up uses the battery like normal. No sudden drops in voltage. But the instant I hook up 120v a few hrs later my battery that was 12.6v drops to like 2.1v. I've changed out my converter already with a new one and this problem still persists any idea what's going on?

[wolfe10]

Are you sure the converter is hooked up properly/proper polarity?


Two different converters giving the same symptoms is unlikely. Before spending more $$, you need to pull out your digital voltmeter and see what is going on.

[Old-Biscuit]

Sorry you are having this issue..........

Can you provide details.
Year/Brand/Model of 'pop-up'??
Converter brand/model

[Mod Edit]

[Torchic]

The new converter I did 1 wire at a time. Only difference was the new one had a ground wire. The old one did charge when i fitst got it, then something happened and not only would it not charge the battery it drained it super fast. I changed the converter and the new one did actually charge the battery, but at this point the battery was shot and only went from like 11.8v to 12.1. I hooked up a new agm battery, drained it to 11.9v, and same thing. Instead of charging, it drained it even faster down to 2v. I did just take it back and got a regular flooded battery today and hooked it up but I didn't see the 13.5v you normally see charging. It stayed at 12.6v. So that's where I am now.

As for model and what not it's a 2007 fleetwood highlander niagara. The converter brand is like warner company or something it's the 8500 series if that helps.

[Torchic]

Actually I just looked it up from my purchase history. The new part that was a direct replacement from the original manufacturer was a WFCO WF-8935 MBA Main Board Assembly

[Old-Biscuit]

1st thing ---should test converter DC output

Open the 120VAC Circuit Breaker that feds the converter
Open Battery disconnect/remove battery fuse on POS cable
Check that the 2 Reverse Polarity Fuses on DC Dist Panel are good
**40A blade type fuse


Disconnect the 2 battery cables from the DC Dist Panel
*******(tape them so they do not make contact/arc)
Battery POS from bottom terminal
Battery NEG from top terminal

*converter cables...leave connected
RED cable to center terminal
WHITE cable to top terminal

Using a Voltmeter test converter DC output
Red probe on bottom terminal where battery POS cable would be connected
Black probe on top terminal where battery NEG cable would be connected

Turn 120VAC CB back on and measure the Converter DC Output
S/B 13.6VDC
IF not....converter is BAD

[Skibane]

Originally Posted by Torchic

But the instant I hook up 120v a few hrs later my battery that was 12.6v drops to like 2.1v.

Due to an installation error, your converter is connected backwards to the batteries.

So, instead of adding current to the batteries in order to charge them, it is subtracting current - thereby quickly discharging them.

[LETMGROW]

Is it possible the battery is hooked up backwards? (Cables Reversed)

[Old-Biscuit]

Just touching the battery cables WRONG (reversed) BLOWS the Converter Reverse Polarity Fuses
If not for those Fuses the converter would be Toast.....Blown up
*Converter can NOT pull from battery and discharge into AC side