Forum Discussion

asifnq's avatar
asifnq
Explorer
May 28, 2014

1989 Pace Arrow Aux Batteries Not Charging

Hi

I have two 6V Aux Batteries that are connected in series and not charging.
I had a bad isolator relay that I replaced butt still no charge. I do measure 14.4V on one side of the relay which is connected to the main battery and the alternator/starter circuit. But the other post of the relay connected to the Aux Batteries shows 12.44V only.
The center post of the relay is connected to the Intellitec Isolator Control like the one in the following link, and intermittently shows 3.5V and drops to 0V.

http://www.intellitec.com/index.php/products/DC_Power_Management/Intelligent_battery_charging/Battery_Isolator_Controller
Class A
  • asifnq's avatar
    asifnq
    Explorer
    Jun 03, 2014
    Hi, thanks for all the replies, it does seem that the battery isolator controller is bad that controls the isolator relay. My new question is then can I not install a toggle switch to manually controll the relay. So whenever I am driving I can manuualy close the relay to charge the coach battery and turn it off after a while.
  • OnaQuest's avatar
    OnaQuest
    Explorer
    May 29, 2014
    SCVJeff wrote:
    If this is like the 85' Pace I had, there is a diode combiner installed up front. Its a heatsink with 3ea. ~1/4-20 studs sticking out. Center to the Alternator, and each side goes to the Chassis and House batteries. Start the engine, measure the voltage on the center stud, then on each side. The sides should be -.6V from the center.

    This is different from the relay that only bridges the batteries for starting

    Fleetwood did away with the diode isolator in 1989. The Intellitec controller that the OP has is evidence of the solenoid being used as the isolator.
  • SCVJeff's avatar
    SCVJeff
    Explorer
    May 28, 2014
    If this is like the 85' Pace I had, there is a diode combiner installed up front. Its a heatsink with 3ea. ~1/4-20 studs sticking out. Center to the Alternator, and each side goes to the Chassis and House batteries. Start the engine, measure the voltage on the center stud, then on each side. The sides should be -.6V from the center.

    This is different from the relay that only bridges the batteries for starting
  • OnaQuest's avatar
    OnaQuest
    Explorer
    May 28, 2014
    asifnq wrote:
    Hi

    I have two 6V Aux Batteries that are connected in series and not charging.
    I had a bad isolator relay that I replaced butt still no charge. I do measure 14.4V on one side of the relay which is connected to the main battery and the alternator/starter circuit. But the other post of the relay connected to the Aux Batteries shows 12.44V only.
    The center post of the relay is connected to the Intellitec Isolator Control like the one in the following link, and intermittently shows 3.5V and drops to 0V.


    Do you have an AUX start switch like the one in this drawing? Will it cause the isolator to close?

    Jumper the small terminal to +12V and see if the isolator closes. If it does, then your Intellitec control is probably defective.

    The controller also is fed from a fuse in the chassis fuse panel when the ignition is on.
  • Artum_Snowbird's avatar
    Artum_Snowbird
    Explorer
    May 28, 2014
    If you put a good jumper across the relay terminals that are supposed to be connecting, and do not seem to be working for you, and it works, then the question is... are the terminals not connecting properly, or is the relay not closing the contacts.

    Once you determine what part is at fault, then you can proceed with correcting it.

About Motorhome Group

38,705 PostsLatest Activity: Jan 22, 2025