On Board Battery Charger

[flugelboneman]

Cougar 27RES: Question: When plugged into external power, do the dual batteries charge? My batteries were down over winter and when I plugged in to shore power my batteries did not seem to be receiving a charge. I only had the coach plugged in for a few hours and wondering if the battery charger within the converter only gives a small charge and it may take longer to top up the batteries.

[bobbecky]

Your converter is the battery charger. With the power cord plugged in and the breaker that feeds the converter is not tripped, if you check voltage at the battery and read about 13.6 volts, then the converter is working. if the battery was completely discharged, then a replacement is likely necessary because it won't hold much of a charge. If you are not reading that voltage at the battery, then you might have a bad converter.

[JRTJH]

If your batteries are lead acid type, and if they were discharged over the winter and if they were subjected to freezing temperatures while they were low charged/discharged, then the plates within the batteries may be warped and damaged beyond the ability to hold a nominal charge.

I'd take the batteries out of the trailer, have them charged on a known good charger and load tested to see if it is the batteries (most probable cause of the problem) before digging into the trailer systems.

That said, keep in mind that if the trailer has been in storage for the winter, there's always a chance that some "critter family" may have invaded and damaged some of the wiring in the trailer.

After taking the batteries off the trailer, a "quick check" of the converter/charger system is to measure the voltage at the battery cable ends. WITH THE BATTERIES DISCONNECTED, the voltage on the battery cable terminals should be 13.6VDC. If that's your reading, I'd suspect it's a battery issue, not a converter issue.

[GlasNav]

Remember to switch your Giggy Box switch to ON, all the way clockwise, if not the current from the converter isn't getting to the batteries!!!!

[NH_Bulldog]

If you left the batteries in the RV and were not connected to shore power, the batteries would discharge within a week or two at most even with the disconnect in the off position. The only way to limit discharge is to completely disconnect the battery cables

[dadnjesse]

Not only will they freeze when discharged if below freezing temperature normal Marine RV lead acid Batteries are not designed to be discharded below a certain voltage and that will weaken them over time.