Forum Discussion

RVimana's avatar
RVimana
Explorer
May 19, 2016

Battery #1 (Engine) vs. Battery #2 (House) Issue

Hi All,
First post on the forums, thanks for taking a minute.

Wife and I were driving our 1988 Honey Class A to visit family, and I inadvertently left the running lights on at the Mother-In-Law. Battery #1 now to low to start engine.

No problem, I'll just switch the leads to Battery #2 (House battery right beside it). No issues the rest of the day - I made certain to turn the lights off, ha-ha.

Hooked up the battery charger from my garage, charged for 24+ hours, checked it with a tester (output 12V+), and reconnected the wires the identical way they came off.

Cranked the engine for about 1/2 a second, then nothing. No lights, no click, nothing.

Switched the cranking battery cables back to the house battery, all good. Engine starts, lights good, everything working fine.

Grab another battery (had one in the garage, checked 12V+), put it in, connect it. Same problem - cranked the engine for about 1/2 a second, then nothing. No lights, no clicks, nothing.

Put the original cranking battery back in and connected it, then hooked up to shore power at my residence for 48 hours, thinking that maybe it might help.

Same problem - cranked the engine for about 1/2 a second, then nothing. No lights, no clicks, nothing.

Not sure where to look. I'm sure I can go out there and switch the battery cables back to the House battery and run along just fine, but that doesn't solve the problem.

Sorry for the long post - any ideas on what to check?

In friendship & safe travels,
RVimana
  • AS the UNIT RUNS FINE UTILIZING THE HOUSE BATTERIES with the chassis wiring.
    I suspect the battery is bad. The spare you used measured 12+ volts.
    12 volts is a discharged battery. Take the battery to a auto parts store and get it tested.
  • Almot's avatar
    Almot
    Explorer III
    Starter battery cables. I had one cracked at the clamp, barely visible, worked until you move it OR until you try to start the engine.

    Dirty/oxidized battery terminal is possible, though after switching batteries back and forth it should've cleaned itself and it is NOT likely to have two batteries with equally bad terminals. Still possible. Wipe it with denaturated alcohol or whatever you have on hand, or clean it with sand-paper.

    Clean and sand those lugs on starter cable too.

    Both batteries dying at the same time? Maybe... Who knows...
  • Rv??

    There are (of course) multiple possibilities here, but I will shoot the easy ones first.

    This sounds like a bad connection problem. Get a battery terminal cleaner and start there. If that doesn't do it, hook up your original main engine battery and try again.
    No Go?
    Feel all the connections you can find and one will probably be warm. Disassemble that one, clean it and put it back together and try again.

    When it is convenient, put both the batteries that did crank on a charger over night and then take them to a local parts store for testing.

    I just spent an afternoon doing this for a boat owner. Since the depression, I have to take any work I can fine.

    Matt

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