12v converter charger troubleshooting

My 12v converter appears to have stopped charging the battery. I went out to go camping recently and I noticed that the batteries were not charging and were almost dead. The batteries are a pair of group 31 deep cycle batteries that were new last April. I pulled the batteries and had the dealer charge them and test them and the batteries are good. How do I troubleshoot the converter?

Quickfarms - I don't know what converter you have, but the battery charging circuit on the ones I know about goes through a pair of 30A fuses that are inside the converter and if either (or both) of these are burned out, the battery will not be charged. They are there supposedly to prevent damage if the batteries are installed incorrectly (reverse wired) but I've found they can fail if you raise the top with the trailer plugged into shore power or do anything else that puts a heavy current draw on the converter.

Those fuses MAY be easy to get to once you open the front panel of the converter, or, they may be wired inline kind of behind the front fuse panel that you'll see when you open it. Here's a link to a thread where I show these fuses on my old, OEM Elixir converter: https://www.hilotrailerforum.com/f28/converter-troubleshooting-and-repair-6454/. Those fuses would be what I check first.

I replaced the Elixir converter with a new one that puts those fuses up front where they need to be.

- Jack

Converter troubles

If is the original converter it may give you peace of mind to change it out. How i knew our converter was bad the lights would dim when the furnice kicked in. On our second HiLo DH just changed it out because it was the original. We purchased the Boondocker converter from Best Converter. Very good customer service. Great technical advice . If you are out camping you can always use your jumper cables from your tow vehicle to your HiLo battery. Also a portable battery pack charger may come in handy for you.

It’s an ELX-45

All the fuses look and test good and the circuit breaker is on

Does the monitor show charging with a fully charged battery

Any other things to check?

There's nothing built-in on the trailer that will show you if the converter is charging that I know of. If you have a multimeter, test the voltage at the battery terminals with the converter ON. If you see voltage above 13V, the converter IS delivering power to the battery. If it's below that, probably 12.5V or less, the battery is NOT receiving a charge.

- Jack

Both of the yellow wires from the converter go to but connectors and to the top terminal on the fuse board

The black battery and the red wire from the master switch go to the bottom bat terminal

Based on the wiring diagram it looks like the converter wires should be connected to the black battery wire and the red wire from the master switch should be connected to the battery terminal

Connecting the black battery wire to the red master switch wire would explain why my master switch does not appear to do anything