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dennislanier's avatar
dennislanier
Explorer
Oct 14, 2015

Converter problem ?

2004 Jayco Class C motorhome . The last couple of nights I have noticed the interior lights dimming and brightening while plugged in to shore power. Also it seems like the furnace blower is changing speeds as well. After doing a little research it seems my converter may be dying. Is it possible for the converter to die slowly as opposed to going all at once? Anything I can check here at the campground with limited tools etc until I get home in a couple of days. Other than running the battery down is there any harm in leaving things alone until I get home? Any help appreciated.
  • shane102 wrote:
    I just had the same symptoms happen to me. Ended up being the converter. I just used my generator for charging batteries and finished trip.


    Converter is a device which converts AC power into DC which is what your lights, gas furnace, etc operate on. The converter also acts as a battery charger. Generator provides AC power which powers converter, air conditioner,electric heaters and other AC devices. To my knowledge a generator is incapable of charging a battery without a battery charger or converter.
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Could be the converter or the battery

    Here is how a battery can do it.. Shorted cell.. When the circuit breaker in the battery positive lead closes the battery draws way more current (due to being only an 8 or 10 volt battery instead of a 12) then it should dimming the lights.. Then the breaker overheats, opens up and the lights brighten. This repeats every period of time.

    Or, it could also be the converter.. You do not know till you test everything

    Simple test: Hook a digital volt meter to the battery terminals and observe

    IF battery voltage less than 13 goes up when lights dim.. It's the battery

    IF battery voltage goes DOWN when lights dim.. Converter.
  • shane102 wrote:
    I just had the same symptoms happen to me. Ended up being the converter. I just used my generator for charging batteries and finished trip.

    If no generator, you could go to town and get a reasonable battery charger to keep batteries charged and worry free for rest of trip.


    Good ideas. We will be leaving tomorrow anyway so I can take care of it when we get home. So far it's still working. I have kept 12v usage at a bare minimum hoping it would help. Thanks to everyone who responded. I will update when I get home so it might help someone else later on.
  • I just had the same symptoms happen to me. Ended up being the converter. I just used my generator for charging batteries and finished trip.

    If no generator, you could go to town and get a reasonable battery charger to keep batteries charged and worry free for rest of trip.
  • dennislanier wrote:
    Thanks for the responses. I will check the connections at the battery and the voltages with my cheapo voltmeter. Hopefully we can stay here 2 more nights before the converter kicks the bucket. I assume the worst that can happen will be battery failure


    Converter fails.......no battery recharging

    No battery recharging..........battery voltage goes down

    Battery voltage goes down......battery life can be shortened if voltage allowed to go below 12.3V
    Damage/major life shortening if below 11.7V
  • Thanks for the responses. I will check the connections at the battery and the voltages with my cheapo voltmeter. Hopefully we can stay here 2 more nights before the converter kicks the bucket. I assume the worst that can happen will be battery failure
  • Dimming/brightening of interior lights.......furnace blower speed changes

    Classic symptoms of failing converter


    120V AC in------converter........13.2V DC output (minimum) steady
    Voltmeter check DC output (on face of converter where cables connect)
  • Sounds like a dying converter to me - that's what happened to my first converter, My second converter eventually went bonkers and put out too much juice - 3rd one has been working fine for many years. If it were me I would check to see if wires are tight and if they are OK then replace the converter - not expensive and you can DIY.
  • Dennis,

    It is unlikely, but such a failure is possible. It is usually caused be a bad connection in the system, so try cleaning and tightening all the connections that you can find first. If that doesn't fix it, then you can panic. (Just kidding..) The connections that are routinely the problem are those at the battery. But check everything. I have even seen the connections on the converter itself go bad.

    Matt

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