Forum Discussion

FireGuard's avatar
FireGuard
Explorer II
Jun 11, 2014

Electrical problem in 03 Southwind 32V

When checking out the MH tonight when I went inside and turned the aux switch on, nothing happened. I could here a relay clicking in the engine compartment.
The 32V has 2 battery disconnect switches over the entry door. 1 says "Main" the other "aux"
I had no 12v power at all and the monitor panel was blank.
I started the engine and about 15 sec later, the interior lights came on and had 12V power. The monitor showed 13-14 volts on both chassis and coach meters.
It also worked fine when the gen was running. If I turned off the engine and gen, I would lose 12V to the coach in about 15 sec.
All batteries are good. Coach batteries are fairly new 6V and showed around 12.3V on the meter.
What do I check next, is there a switch or relay that controls the transition from engine or gen to the coach system?
Class A
  • wildmanbaker's avatar
    wildmanbaker
    Explorer
    Jun 11, 2014
    12.3 volts on the house batteries, means they are about 1/2 discharged. 12.0 volts is considered completely discharged. 2, 6 volt batteries should read about 12.6 fully charged.
  • enblethen's avatar
    enblethen
    Nomad
    Jun 11, 2014
    Under the hood driver's side is where the battery control center is located. Clicking could be from the charge relay or the ignition relay.
    The battery disconnect relay is a louder click then the other relays.
    Cycling the relay from the switch indicates that there is power. It does not mean the contacts are closing.
  • darsben's avatar
    darsben
    Explorer II
    Jun 11, 2014
    Another possible cause could be corrosion inside the Aux switch under the hood. I had a similar problem with my switch. Took it off (disconnect power first) and removed the screws holding the top and bottom of switch together. Clean the big washer that is in there and the two brass contacts. this may cure the problem
  • FireGuard's avatar
    FireGuard
    Explorer II
    Jun 11, 2014
    Thanks for the good info. I will check those items.
    When I checked battery voltage, everything was off so the batteries seem to be good.
    When I cycle the disconnect switch for the aux system I can hear a relay clicking in the engine compt in front of the drivers seat.
  • enblethen's avatar
    enblethen
    Nomad
    Jun 11, 2014
    There is normally a fuse or circuit breaker adjacent to the batteries in line that goes to battery disconnect. Circuit breakers may have a reset. These are the small one inch cube style with two posts.
    Yes, the battery disconnect could have bad contacts. These latching relays are more then $20 and could be hard to find. You should be able to test them. Use a meter on the battery side, then energize the relay, the voltage on the coach side should be the same.
    Your battery charge system is working properly as 10-15 seconds for it to engage is correct.
  • Dale_Traveling's avatar
    Dale_Traveling
    Explorer II
    Jun 11, 2014
    With the coach engine running you are getting 12VDC from the engine alternator. With the generator running or on shore power you getting power from the convertor. A possible problem is the battery disconnect solenoid contacts are bad. But before you start spending money do a good cleaning of the battery posts and terminals. Then check the grounds between the battery and the coach frame. If all the tie points look good then dive into the battery control center ensuring all the tie points there are clean and tight. If that doesn't fix the problem then I think the solenoid has failed. Easy fix and costs around $20.

    But first do as Dog Trainer suggested and check the batteries at the posts not the terminals. Yes it makes a difference. One dirty terminal of the battery pair will cause problems.
  • Dog_Trainer's avatar
    Dog_Trainer
    Explorer
    Jun 11, 2014
    It sounds like the batteries may be bad. The voltage you are reading seems to be comming from the charger or converter when you have alternator or den. power. Have you checked the battery at the post with the gen. and shore power off.

About Motorhome Group

38,707 PostsLatest Activity: Feb 20, 2025