Forum Discussion

Lynn608's avatar
Lynn608
Explorer
Sep 16, 2017

no 12volt in coach-only when plugged into tow vehicle

Hi all.. hope everyone is safe from Irma. Here is my sad story..

While running from Irma we pulled into a Walmart parking lot to sleep for an hour. Went into our 2016 Forest River MicroLite 25KS travel trailer. No 12 volt power at all.. even tho the battery was up. Jack and jack light worked fine.
Plugged trailer back into tow truck and bingo.. all good 12 volt even fridge. We arrived at camp and plugged into 110 and all was good.. 12 volt system worked fine.

After thinking about it I asked dear hubby to check the converter (bad idea) he flipped the breaker switch to the converter and the whole 12volt system went off and would not come back on. Went and bought a new breaker switch just in case but nothing changed.
We spent the rest of the week plugged into the truck so we could keep the fridge cold and used the main 110 power for all else so as not to drain the truck battery.
So.. what do you think. Why did the battery not run the 12volt system when the truck pigtail would.. and .. we've checked the battery, connections, ground etc and all good. Have we now also killed the converter or is there a reset or something?

Look forward to hearing your thoughts...
Thanks
Lynn
  • bikendan's avatar
    bikendan
    Explorer
    Sep 16, 2017
    Probably tripped the resettable circuit breaker that's usually tucked along the A-frame.
    It has a tiny black button that you press to reset it.

    It's a small gray/silver box with the black button.
  • Ivylog's avatar
    Ivylog
    Explorer III
    Sep 16, 2017
    Your battery is bad/shot/needs water or bad connections.
  • Lynn608's avatar
    Lynn608
    Explorer
    Sep 16, 2017
    Thanks bikendan for getting back to me.. when you say A-Frame.. is that located inside the fuse box area or somewhere else ... sorry to be so dumb..
    Lynn
  • westend's avatar
    westend
    Explorer
    Sep 16, 2017
    Follow the positive battery cable back, from the battery. There should be that circuit breaker within a few feet. Yes, it's sometimes in a junction box, tucked inside the frame. If it has a button, it's a manual reset breaker. If it is just a metal can, it is self-resetting. Replacements are available at auto parts stores.

    How are you determining your battery is good and charged fully? Do you have a hand-held meter?

    If your converter is not outputting charge current, it may have a fuse blown. Check the 12V fuse panel or on the converter, itself. These fuses will typically be higher amperage--40, 30, or 20 amp fuses. Again, available at auto parts stores.
  • Lynn608's avatar
    Lynn608
    Explorer
    Sep 16, 2017
    Thank you very much... there is a metal junction box which Dear Hubby will go into when his vertigo wears off from going under the A-Frame today.. We've determined the battery is good as the jack and the jack light work just fine.. we will try another battery tomorrow tho just in case. Will also check fuse box but I think we determined the fuses were all good.
    Thanks again.
    Lynn
  • SoundGuy's avatar
    SoundGuy
    Explorer
    Sep 16, 2017
    Lynn608 wrote:
    ... there is a metal junction box which Dear Hubby will go into when his vertigo wears off from going under the A-Frame today..


    Most circuit breakers used on recreational trailers are thermal, auto resetting - like this ...



    Only a few $ ... 30 amp will do for most trailers, 'though if the original is stamped with a rating just replace it with another of the same.
  • westend's avatar
    westend
    Explorer
    Sep 16, 2017
    Lynn608 wrote:
    Thank you very much... there is a metal junction box which Dear Hubby will go into when his vertigo wears off from going under the A-Frame today.. We've determined the battery is good as the jack and the jack light work just fine.. we will try another battery tomorrow tho just in case. Will also check fuse box but I think we determined the fuses were all good.
    Thanks again.
    Lynn

    You owe it to yourself to buy a 12V test light and/or a hand-held meter. The meter is usually better choice as you can measure voltage/resistance. The learning curve is very mild for learning how to use a meter.

    Without either tool, tracing the path of electricity and it's presence is problematic. If you have a loose 12V bulb and some wire, you can fabricate your own test light but they are under $5 at most stores.
  • Captain_Happy's avatar
    Captain_Happy
    Explorer
    Sep 17, 2017
    If your jacks work, I don't buying another battery is going to fix your problem. You need to get an volt-Ohm Meter, and learn how to use it. Another question, does your rig have a battery disconnect switch located somewhere that's turned off?

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