Forum Discussion

chefdc1's avatar
chefdc1
Explorer
Nov 07, 2016

Coach Battery issue, no power

I decided to check the water in the coach battery today. Disconnected battery, checked water, added a little, re connected. Now the 12 volt power is not working. Everything (except battery and tank level meters) works with shore power or generator.
I checked the fuses. Both 30 amp seemed blown so I replaced them. All of the 15's were fine and the breakers were fine.
Everything worked fine before I started this project.
Any advice is welcome.
Class C

10 Replies

  • Bordercollie's avatar
    Bordercollie
    Explorer
    Nov 08, 2016
    Make sure that you did not leave a small gage wire with a ring terminal disconnected when re-connecting main cables to battery terminals.
  • wrgrs50s's avatar
    wrgrs50s
    Explorer
    Nov 07, 2016
    If you accidentally arced the battery it may be the fuses on your 110 to 12 volt converter. Not the fuses in the fuse panel. You will have to locate the converter and you should find 2 fuses on the back of the converter. They are there to protect it in the event of reversing the cables.
  • ksg5000's avatar
    ksg5000
    Explorer II
    Nov 07, 2016
    Another possibility. There is usually an auto reset circuit breaker close to the batteries (google as they don't look like typical fuse/breaker) if they go south then the batteries as essentially disconnected from the rig. There not expensive and available at any auto parts house.
    .
    Also - your rig likely has a battery disconnect switch - mine is up front near the drivers left knee - sometimes they are near the main entry door.
  • AJR's avatar
    AJR
    Explorer
    Nov 07, 2016
    My battery disconnect switch blows a fuse on the battery disconnect relay every time I try to re-connect the battery backup. I have given up why. I just replace the 5A fuse and all is good again.
  • enblethen's avatar
    enblethen
    Nomad
    Nov 07, 2016
    Recheck for battery disconnect
    Look around battery for dropped cable
    Look adjacent to the batteries for a circuit breaker or fuse.
    Make and model of rig would help!
  • jrobert01's avatar
    jrobert01
    Explorer
    Nov 07, 2016
    Check fuses in inverter.That happened to me once took forever to find it.
  • chefdc1's avatar
    chefdc1
    Explorer
    Nov 07, 2016
    I have three cables. Red is on positive, black and green on negative. I don't think I have as battery disconnect switch. Multi meter shows 12 v at terminals.
  • tobydad's avatar
    tobydad
    Explorer
    Nov 07, 2016
    Start with the simplest first - Battery cables connected correctly (positive and negative) - Battery cables tight enough that you cannot wiggle them around the post - Battery disconnect switch turned on.

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