Forum Discussion

Seminoe_Joe's avatar
Seminoe_Joe
Explorer II
Sep 09, 2023

Help! Lance 850 isn’t getting power from truck battery

Just installed a new camper side plug because the old one was damaged. Connecting everything right, camper was drawing power from the truck yesterday when I left home. Last night and today, no dice. The driving lights all work, so the plug’s not the problem. A voltmeter tells me that the wire in the camper is getting 14.6 volts when the truck is running. Looking around for any fuses or breakers that might be bad, but all is good. So…what the heck is going on here?! Anyone experience this before? Any suggestions for what to try?
Truck Campers
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Sep 09, 2023
    OK on alternator but not battery suggests bad battery or connection. Load test the battery and test the voltage from the battery posts - (not the cable connection) to frame ground and battery post + to the 12V wire to the camper.
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Sep 09, 2023
    And a failure after a repair suggests to check the repair, don't assume the new connector is still OK. ie In particular the lights working is not the 12V charge line.
  • Seminoe_Joe's avatar
    Seminoe_Joe
    Explorer II
    Sep 09, 2023
    Just to clarify: the camper interior lights and tv, etc were working off the truck battery (truck running) when I switched off the house battery switch in the camper. Now, when I run the truck and switch off the house batteries, nothing is working from the truck battery. But a voltmeter applied to the connector wire indicates plenty of juice. So the repair worked. Electricity is coming in from the pigtail. It’s just not making it to anything else. I’ll keep probing with the voltmeter and see what I can find I suppose.
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Sep 09, 2023
    Volt meter tests can be misleading because they virtually draw no amps. Test with a load.
  • opnspaces's avatar
    opnspaces
    Navigator II
    Sep 09, 2023
    It's too early in the morning for me to process and give an idea what's happening. But my suspicion is somehow you are miswired and have intermittently 12v positive on the ground wire. So you can read 12v in the camper but that 12v can't get out of the camper because there is 12v positive on on the ground.
  • mkirsch's avatar
    mkirsch
    Nomad II
    Sep 11, 2023
    Flipped the switch, it worked. Flipped the switch again, and it didn't work...

    I would suspect the switch.
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Sep 11, 2023
    Check for reverse polarity. Connect a long wire to the truck frame and measure the voltage in the camper. Ground should be 0V and positive 12V.

    Then using the same ground connection turn on lights and track down the 12V disconnect. l'd double check the ground again. A voltmeter will read OK with a high resistance connecton without a load because the voltmeter draws virtually no load.
  • Seminoe_Joe's avatar
    Seminoe_Joe
    Explorer II
    Sep 11, 2023
    opnspaces wrote:
    It's too early in the morning for me to process and give an idea what's happening. But my suspicion is somehow you are miswired and have intermittently 12v positive on the ground wire. So you can read 12v in the camper but that 12v can't get out of the camper because there is 12v positive on on the ground.

    The white wire is the ground and I wired it to the ground. Black is positive and I wired it as such. As I mentioned before, everything was working for the first few hours of the trip, then somewhere along the line, it stopped working. Is the battery seperator in a 2012 Lance susceptible to failure? I was thinking it was somehow shutting off the charge coming in from the truck battery.
  • EricCO's avatar
    EricCO
    Explorer II
    Sep 11, 2023
    Just double checking on this...

    Are you checking all this with the truck engine running and the truck camper battery disconnected at the battery posts?
  • Seminoe_Joe's avatar
    Seminoe_Joe
    Explorer II
    Sep 11, 2023
    EricCO wrote:
    Just double checking on this...

    Are you checking all this with the truck engine running and the truck camper battery disconnected at the battery posts?

    Truck running, camper batteries still connected but kill switch flipped. I’ll disconnect the batteries and check again.

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