Battery Life

IF you are going to have to replace the batteries,,,,,
Go to Sams club, Costco, Batteries + or wherever to get 2 six volt golf cart batteries instead of the standard rv/marine batteries, cost wont be but about $20 more, and they will give you twice as much usable power before you start damaging them from over draining, and should last longer.
NOTE you do have to change how they are wired when you install them. Come back here and guidance will be given.

and don,t buy auto batteries, there not for rv.s

An even more basic test but I didn't want to edit what was above.

With the shore power plugged in take a voltage reading at the battery (steps 1 and 2 above)

If the reading is higher than 13 volts your batteries are receiving a charge from the shore power cord.

If you have solar on the trailer then disregard and let us know so we can advise further.

Simple way...unplug from shore power, set meter to 200 DC (mine, have not seen the HF cheapie) and check battery. Red probe to pos, and black to neg post. Remember reading (mine, likely 12.8 to 13 volts).

Now plug into shore power, go back, do the same, set meter same, touch probes, if charger is working, should see 13.2 to maybe 14v.

A digital meter is nice, not sure what you have.

Jerry

opnspaces has you dialed in with the multi meter. FYI, a battery can show a good charge but fail a load test so taking them to your nearest auto parts store to get tested or buy the HF version and it will help confirm bad batteries. Check the fluid levels.

Assuming you have the same or similar meter, I circled the important parts in yellow.

Turn the knob to DCV 20. That indicates you want to measure DC voltage and no more than 20 volts. (Typically set the voltage to the nearest voltage you expect while rounding up)

Plug the red test lead into the middle port
Plug the black lead into the bottom port.

Turn the meter on.

unplug the shore power cord for the trailer.

1. Now touch and hold the pointy end of the red test lead to the positive or (+) post on the battery
2. Touch and hold the pointy end of the black test lead to the negative or (-) post on the battery

This is your battery voltage. Write it down.

Now plug the shore power cord back in.

Repeat the two steps above to take a second voltage.

If your system is charging you should get a higher voltage at the batteries.

If needed post your two voltage measurements and we can help you determine if it's charging.

Read the display for your voltage.

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