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  • 8v92 alternator not charging

    Posted by Archived on October 29, 2017 at 11:29 pm

    Gentleman,

    After three uneventful days on the road the red light comes on the dash notifying me the alternator is not charging. Chassis batteries are down by about half at the end of the day but rig runs fine. Verified no charging voltage with voltmeter. I’m parked for a couple months in Phoenix but need to get working on this. Where do I start? Thank you all. BG

    Greg replied 8 years, 11 months ago 5 Members · 4 Replies
  • 4 Replies
  • Fred F.

    Member
    October 30, 2017 at 6:31 am

    Well you need to verify the alternator you have to charge the batteries, then verify if it has a external regulator or not….Then you can check to see if the regulator is giving the alternator the charge command….how many wires are hooked up to the alternator or a pic would help to identify this as well..

  • Art

    Member
    October 30, 2017 at 4:40 pm

    Like Jeff said there are things to check. Assuming you verified there alternator has no output, the next simple check is to jumper battery voltage to the field wire on the regulator and see if you get alternator output.

    Be careful you only leave the jumper on long enough to get the information because if it is the regulator, powering the field wire allows the alternator to put out unregulated high voltage.

    After that it gets more complex and expensive. If my memory is correct there was an issue with the field wire disconnecting from the alternator field wire terminal. You have to access that through the bedroom floor or from under the coach. If the wires are attached you can check batteries, but I suspect the alternator would more likely be the problem.

    The alternator can be replaced without going through the house, but it is a hard job made marginally easy if the shop has hoists and can move the coach up and down as needed to assist with the removal and replacement. The job is difficult.

  • Harry

    Member
    November 23, 2017 at 2:03 pm

    Trouble shooting reveals no power to the voltage regulator with ignition on and engine running. Can anyone tell me where the Ver gets its power and is the a relay or breaker involved.

    Thanx buds.

  • Greg

    Member
    November 23, 2017 at 6:22 pm

    I think your vintage coach used a black cast metal enclosed voltage regulator mounted above the chassis batteries and it might have had 4 wires. A battery wire (positive), a field wire, a relay wire, and a ground.

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