Yep...just make sure your multi-meter has at least a 10 amp capacity for amp draw. Useful for testing parasitic draw on just about anything that uses DC power. Lots of videos online for testing parasitic battery drain.
It sounds to me like the new batteries were installed wrong. Switch the refer to propane, recharge the batteries and try that for a few days. What runs the water pump and lights ?. Maybe its time for solar panels. Good Luck
- What is the make and type? ( Example.. Interstate, 12VDC, 85Ah, or (2) 6 volt batteries)
- Check the batteries for proper water level
- 2 battery cables: Are they White and Black or Red and Black?
If it is White and Black the white cable should be connected to the NEGATIVE battery terminal and the other end should be connected to the TT's FRAME (Ground)
The BLACK cable should go to a 30 amp inline main fuse located near the battery and then into usually a 4x4 electrical box where it connects to the battery charge controller in the TT
Batteries are Nautalis 12volt deep cycle batteries. Run fridge and lights and water pump off it. Checked and hooked up properly. Went through new ones in one day, returned them and went through a second set of new ones in one day again. Hooked up to one solar panel per battery during day.