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idtrout1's avatar
idtrout1
Explorer
May 18, 2021

electrical I think

My son has a pop-up trailer I'm not sure of make or model but here is the problem. When he is plugged into 110 volt (shore power) the lights and heater and everything works fine. However when he is dry camping he has no lights and nothing works. He has checked the battery etc. So my question is where do you start looking for the problem. Are there fuses in there somewhere that is blown and not letting power from battery travel to lights etc. Thanks and suggestions will help and be a starting point.
  • Lights and heater are typically 12v.

    Presumably when hooked up, the charger is providing 12v directly. Look for the connection from the battery to the system. Most likely a disconnect switch but could be a broken or loose connection.
  • Look up the owners manual if there is one available. There may be a switch to turn on or a breaker. Turn on a light switch and put a voltmeter across the battery to see if the voltage is holding up. It could be a very bad battery.

    While on shoreline the Converter supplies power and usually charges the battery but if it is shot it may not take a charge.
  • This may be a dumb question, but did he check the battery cut-off switch? It's not always in an obvious place. Though in a popup, it's probably on or near the battery box (if there's a cutoff switch at all), so it would be hard to miss.
  • Check for Inline fuse or DC CB on/under the tongue/frame ----follow the Battery POS Cable


    If it was the Reverse Polarity Fuses on Converter he would not have ANY DC whether on shore power or not
  • Often the battery gets hooked up backwards, blows a fuse near (inside) the converter.
  • Fuse or circuit breaker.
    There could be one adjacent to the battery, sometime in junction box where TV cable meets battery cable and the trailer wiring.
    Next location is in the 12 volt DC distribution panel. This quite often is behind metal plate next to the 120 volt circuit breakers.