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Soju's avatar
Soju
Explorer
Aug 15, 2014

No power to trailer when battery is connected

I have a 2011 Milan Eclipse 5th wheel and am experiencing some electrical problems. I just returned from a 10 day trip and everything worked great. At home, I plugged the trailer on to "shore" power while unloading and all the electric components were working (ie air conditioner etc). I turned everything off after I was done unloading. An hour later I came out to the trailer and nothing electric was working...trailer still plugged in to shore power (30 amps).

Here's what I've done so far in terms if troubleshooting:
1-fuses and circuit breaker are all good (even the fuses behind the converter IOTA 45)
2-disconnected the battery and the charge is good
3-could not find any inline fuses by the battery
4-with the battery disconnected, the trailer's electrical system is fully functional when connected to shore power
5-I reconnected the battery and nothing works with or without shore power connected

I can't figure out why the trailer gets power when hooked up to shore power but as soon as I hook up the battery, nothing works.

Battery is connected correctly...

Any suggestions are greatly appreciated.
Thanks
Matt

5 Replies

  • Thanks for your help guys. It was the battery disconnect switch. I just bi-passed the switch and everything works.

    Matt
  • Almot's avatar
    Almot
    Explorer III
    3 - it should be in the first few feet of the red Pos battery wire.
  • Thanks for the advice. I'll check the ground wire and the battery cutoff switch. I checked that battery with a multi-meter (12.4 v).

    Matt
  • Follow the negative cable to the ground. Its usually in a spot where it gets blasted with the water road dirt etc. Take it off and wire brush everything. Re install then spray with bettery terminal protectant. Do this after you disconnect from battery. BYW did you check to see of the battery is dead??
  • Do you have a transfer switch for a generator in the Milan? About the only thing, given the statements made, is that both 12V and 120V systems are being interrupted by the 12 volt power of the battery,i.e. a relay or solenoid.
    If your battery has sufficient charge, the lights in your 5'er should be functional. How are you measuring the voltage of the battery?

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