Batteries charging with motor running
We have a 2015 Thor Tuscany. While running down the road with fridge on and inverter on, batteries do not charge. They charge just fine while on shore power or generator. Am I missing something? Help!
Forum Discussion
When I had this happen to me on my RV,the alternator was not charging the house batteries,I found that the CONTINUOUS DUTY SOLENOID had failed.
When you start your RV the voltage should go up to 14.4 or so then within a few seconds the solenoid will click and you will get power to the house batteries.If you can find it it is easy to check with a simple volt meter. The "battery isolator relay" (which is sometimes also used as an "emergency start relay) is a VERY common failure point.
Often, you don't even notice that it is no longer passing any charging current from your chassis battery to the house batteries while driving, because your house battery charger still recharges the house batteries after you arrive at your destination.
If it's still working properly, you will hear it "thunk" as it activates when the ignition switch is turned on, and you will measure almost exactly the same DC voltage on both of its large connection studs while the motorhome engine is running.
No "thunk" = relay coil is burned out, or isn't receiving any voltage
"Thunks", but big difference in voltages at its studs = Electrical contacts inside it are burned or corroded
When you start your RV the voltage should go up to 14.4 or so then within a few seconds the solenoid will click and you will get power to the house batteries.If you can find it it is easy to check with a simple volt meter. The "battery isolator relay" (which is sometimes also used as an "emergency start relay) is a VERY common failure point.
Often, you don't even notice that it is no longer passing any charging current from your chassis battery to the house batteries while driving, because your house battery charger still recharges the house batteries after you arrive at your destination.
If it's still working properly, you will hear it "thunk" as it activates when the ignition switch is turned on, and you will measure almost exactly the same DC voltage on both of its large connection studs while the motorhome engine is running.
No "thunk" = relay coil is burned out, or isn't receiving any voltage
"Thunks", but big difference in voltages at its studs = Electrical contacts inside it are burned or corroded
