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jk31668's avatar
jk31668
Explorer
May 11, 2016

E450 CLASS C CHARGING ?

have a 2010 sunseeker 31' class c. does anyone know...do both the house battery and the engine battery get charged when the motor is running? thanx
  • They should but don't know about yours in particular.
    Can easily be determined using a volt meter.
    Maybe find an electrical person to help you if need be.
  • Depends on how the coach manufacturer wired it. You have to test it to see.

    1. Use a VOM to check the voltage of the house battery. Should be about 12.7v if fully charged.
    2. Start vehicle, then re-check house battery voltage. If charging, the voltage should be somewhere between 13.6v and 14.4v.

    If the voltage goes up, it is being charged. If the voltage does not go up, it is not being charged.

    I suspect 95% or more do have the house battery being charged.
  • Almost RV's are set up with a solenoid switch device that charges both the starting battery and house battery while driving for some distance/time . When engine is running you should read around 14 volts at starting battery terminals and around 13.6 volts at the house battery terminals. Set your digital multimeter to the 20volts DC scale. Note: Most RV converter/chargers will not charge the starting battery unless there is a special after market device installed. Google "Trik-L-Start"
  • The short answer is YES. It was designed that way. Could something have failed such that both battery banks are not being charged by the alternator-- sure.

    Bobbo gave you the starting point for verifying that your system is working as designed.
  • JK,

    As you have seen, the answer should be, yes.
    Note: Should Be....

    I have never known of an MH that did not as built, but that does not mean that the contactor (word for BIG relay) or combiner that does is still functioning.

    As said, check it with a meter. If you aren't charging the house bank you will have to find where the part that does this is located.

    Matt
  • Depending on the charge relay used, some of them only connect the coach battery for charging after the starting battery reaches a certain level, so you might not see the coach battery charge when you first get going.
  • Google "12 volt battery tester" Get the one that goes into the 12 volt power port of the dashboard. Put in the port with the engine off.....it should read 12.75 volts or near that. Start the engine and it should go from 13-14 volts. Means it's charging the engine battery. Shut off the engine and put in a power port in the motorhome area. It should read 12.75 volts, again start the engine and it should jump up to same reading as the front 13-14 volts. Means it is charging the house batteries. Do you have a generator? if so shut off the engine, start the generator and see if the meter jumps again to 13-14 volts and the generator is also charging the batteries also. Good luck
  • Mine is a 2010 as well and yes it charges the house batteries while running the engine.
  • bobthegod wrote:
    Google "12 volt battery tester" Get the one that goes into the 12 volt power port of the dashboard. Put in the port with the engine off.....it should read 12.75 volts or near that. Start the engine and it should go from 13-14 volts. Means it's charging the engine battery. Shut off the engine and put in a power port in the motorhome area. It should read 12.75 volts, again start the engine and it should jump up to same reading as the front 13-14 volts. Means it is charging the house batteries. Do you have a generator? if so shut off the engine, start the generator and see if the meter jumps again to 13-14 volts and the generator is also charging the batteries also. Good luck


    X100 .... an outstanding piece of advice!

    Going a little further and for what it's worth: I have two voltmeters on the dash of our Itasca Class C motorhome - one plugged into the stock Ford 12V dash receptacle and another Velcro'd onto the dash with it's input plugged into a 12V receptacle back in the coach.

    One voltmeter shows the approximate voltage of the engine battery all the time. The other shows the approximate voltage of the coach batteries all the time.

    Both meters read over 14 volts when driving down the road .... meaning that the alternator is charging both sets of batteries. When parked with the engine OFF both meters show the approximate voltage of the two battery sets, which of course differs for each battery set .... with the two voltmeters reading in the 12 volt to 12.8 volt range if everything is normal and working as it should.