Forum Discussion

ACDNate's avatar
ACDNate
Explorer
Apr 14, 2018

12v power issue

2008 Winnebago Journey 39z.

New issue presented itself today. Randomly half of the 12v powered items in the coach have no power. Everything working one moment. Was out of the coach for 20min and when I went back in half not working.

I've got 12v power to stereo's, awnings, some lights. I don't have 12v power to main lights, control panel that shows power status, tank levels. I do have power to thermostat (assuming it uses a 12v power supply for something), the water pump powers.

Checked all 12v breakers, house and chassis. None tripped

110v power good weather on shore power or generator.

Buddy who's had similar issues before said there's a solenoid that dispenses 12v power to the coach that can stick. He recommended turning on generator and then off to work the transfer switch and activate the solenoid. Did that a couple times and 12v power came back.

40 min later I lost half 12v power again.

Tried turning off house batteries with switch at door. This turned off the remaining 12v items on. Turned back on after a short time and still have only half 12v power.

Are there more than 1 solenoids that control 12v power? I notice there are 2 button breakers for 12v power to the inside 12v panel.

Any suggestions what else to look at?

Thanks,

Nate
Class A
  • Scottiemom's avatar
    Scottiemom
    Nomad
    Apr 15, 2018
    ACDNate wrote:
    Teacher's Pet wrote:
    Our Tiffin has had that happen quite a few times ... check the inverter breakers, when we loose the 12 volt power from the bath forward on the passenger side..that has always been the cause.


    Oddly enough, resetting the inverter/converter breaker turned things back on.

    Is this a sign of the inverter/converter going bad?


    Nope. . . when it happens as Teachers Pet described it's because I for got to turn off one of the electric heaters and started up my hairdryer while he was toasting his bread. It's just too much (extra) on one circuit.

    Dale
  • YC_1's avatar
    YC_1
    Nomad
    Apr 15, 2018
    ACDNate wrote:
    What I found odd is that half the 12v works. So this solenoid will have 2 outputs?


    No, it is a very simple on/off switch so technically it does not have an input and output. It just shorts the two large connectors together.

    Your symptoms of resetting the inverter does NOt add up to losing 12 volt lights. But if it works, so be it.
  • enblethen's avatar
    enblethen
    Nomad
    Apr 15, 2018
    Have you verified that the circuit breakers are making internal contact?
    What items are not working?
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Apr 14, 2018
    When you say "Half" do you mean like
    Marker lights, Tail, turn and such work but Indoor lights do not?

    Motor homes have two 12 volt power systems. ONe for the MOTOR part one for the HOME part

    Motor part may inlcude jacks and steps. It will include all exterior lights save for the porch and Work and any "Scare" lights you have (Basement lights are indoors) This includes Tail, Stop. Turn, Marker/clearance parking fog driving and headlights..

    It may even include SOME lights inside (Dash lights and "Dome" light over the dash)

    House is most all the indoor lights, Porch, Work and Scare.
  • ACDNate's avatar
    ACDNate
    Explorer
    Apr 14, 2018
    enblethen wrote:
    Does your 12 volt DC actually have circuit breakers and not fuses?


    For the coach all 12v push button circuit breakers. The chasis does have some traditional fuses.
  • ACDNate's avatar
    ACDNate
    Explorer
    Apr 14, 2018
    Teacher's Pet wrote:
    Our Tiffin has had that happen quite a few times ... check the inverter breakers, when we loose the 12 volt power from the bath forward on the passenger side..that has always been the cause.


    Oddly enough, resetting the inverter/converter breaker turned things back on.

    Is this a sign of the inverter/converter going bad?
  • Teacher_s_Pet's avatar
    Teacher_s_Pet
    Explorer
    Apr 14, 2018
    Our Tiffin has had that happen quite a few times ... check the inverter breakers, when we loose the 12 volt power from the bath forward on the passenger side..that has always been the cause.
  • ACDNate's avatar
    ACDNate
    Explorer
    Apr 14, 2018
    What I found odd is that half the 12v works. So this solenoid will have 2 outputs?
  • YC_1's avatar
    YC_1
    Nomad
    Apr 14, 2018
    ACDNate wrote:
    That was my first inclination. My gut says a solenoid isn't activating. That theory would indicate the system is split though since I do have some 12v working.


    Very common. Have someone toggle the switch and locate the solenoid that is being controlled. Use a test light on each large connection and when it acts up check them again. I bet one side is out.

    Many people just bypass the solenoids.

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