2001 Alternator

Discussion in '2nd Gen DIY' started by Jimmy68, Sep 9, 2016.

  1. Jimmy68

    Jimmy68 Senior Member

    Posts:
    1,402
    Likes Received:
    633
    Joined:
    Aug 30, 2015
    Location:
    Lethbridge Alberta Canada
    Ram Year:
    2001
    Engine:
    5.2L Magnum
    Driving home tonight the volt gauge pegs at 18V. Assuming my alternator effd up I was pulling over to give it a good smack. Got stopped and it smartened up.
    So Im thinking the brushes are bad and thought I had two spare alternators at home. Nope. A 94 and a 99 are different than my 01. Like to make them work if I can.

    Anybody know how to rewire my truck.
    Where would I find a rebuild kit for my alternator.
    (my question marks dont work) (neither do my apostrophes)
     
  2. dudeman2009

    dudeman2009 Senior Member

    Age:
    22
    Posts:
    1,457
    Likes Received:
    166
    Joined:
    Feb 9, 2016
    Location:
    Lansing, Michigan
    Ram Year:
    2001 1500 Sport with enough electrical modifications to make my brain hurt
    Engine:
    Magnum 360
    First, try to recreate the problem while a multimeter is attached. Also, check your battery for loose or corroded connections, that can cause high charging voltages as well.

    18.6V is very high, i'm surprised nothing was damaged and bulbs aren't burnt out after that, especially given the time it must have been acting up for you to have started to pull over.

    Did the lights change intensity? PCM trouble codes (i'm pretty sure too high a charging voltage will throw a code)? What were you reading the voltage off of, factory gauge, aftermarket?
     
  3. Jimmy68

    Jimmy68 Senior Member

    Posts:
    1,402
    Likes Received:
    633
    Joined:
    Aug 30, 2015
    Location:
    Lethbridge Alberta Canada
    Ram Year:
    2001
    Engine:
    5.2L Magnum
    Didnt act up all day today. Drove maybe 4 hours. Battery is good, etc. Luckily the CHECK GAUGES light came on with a soft bing bing bing of the alarm bell.
    Was daytime so I saw no light increase, no codes, factory gauge.
    Reman here is $185-$225 plus tax. Used at wrecker is $35 wholesale, $50 retail with 90 day warranty.
    Cheap enough to buy a used one
     
  4. meistermash

    meistermash Member

    Posts:
    48
    Likes Received:
    2
    Joined:
    Aug 23, 2013
    Location:
    WY
    Ram Year:
    2001
    Engine:
    5.2
    It's a ground.
    Had that exact issue.
    Cleaned the terminals, cleaned the ground and ran extra ground wires.
    One to the alt case itself.
    I rebuilt my stock alt and turned the comutator prior to that.
    I got the rebuild kit online and I think I searched Denso to find it.
    The Commutator was wayout out of wack.
     
  5. Jimmy68

    Jimmy68 Senior Member

    Posts:
    1,402
    Likes Received:
    633
    Joined:
    Aug 30, 2015
    Location:
    Lethbridge Alberta Canada
    Ram Year:
    2001
    Engine:
    5.2L Magnum
    Thanks. I know my ground to the battery is loose. Loose enough to wiggle off anyway. Has been for a year or better. Helps when working on the truck, makes a lazy way of taking it off.

    Have yet to have the issue repeat itself. Still same alternator.
     
  6. meistermash

    meistermash Member

    Posts:
    48
    Likes Received:
    2
    Joined:
    Aug 23, 2013
    Location:
    WY
    Ram Year:
    2001
    Engine:
    5.2
    Yep.
    Would only do it every now and then to me.
     
  7. Jimmy68

    Jimmy68 Senior Member

    Posts:
    1,402
    Likes Received:
    633
    Joined:
    Aug 30, 2015
    Location:
    Lethbridge Alberta Canada
    Ram Year:
    2001
    Engine:
    5.2L Magnum
    It's one of those things that's going to resurface in a blizzard. Lol.
     
  8. Jimmy68

    Jimmy68 Senior Member

    Posts:
    1,402
    Likes Received:
    633
    Joined:
    Aug 30, 2015
    Location:
    Lethbridge Alberta Canada
    Ram Year:
    2001
    Engine:
    5.2L Magnum
    Did it again today. Several times. All I did was shut the engine off and turn the key back on. Engine would fire up and charge fine for another mile. I wasn't even stopping, just going 70mph, shut it off in gear and turn it back on. Tomorrow I'm buying an alt.
     
  9. Jimmy68

    Jimmy68 Senior Member

    Posts:
    1,402
    Likes Received:
    633
    Joined:
    Aug 30, 2015
    Location:
    Lethbridge Alberta Canada
    Ram Year:
    2001
    Engine:
    5.2L Magnum
    Got a new to me one for $25 with 120 day warranty.
     
  10. dudeman2009

    dudeman2009 Senior Member

    Age:
    22
    Posts:
    1,457
    Likes Received:
    166
    Joined:
    Feb 9, 2016
    Location:
    Lansing, Michigan
    Ram Year:
    2001 1500 Sport with enough electrical modifications to make my brain hurt
    Engine:
    Magnum 360
    You did check for corrosion on the battery and alternator terminals right?

    If not, there are a couple things that could cause high charging voltages. Make sure you check the voltage sense and excitement wire on the alternator (its a 2 pin connector) If that is loose or corroded, it will cause this problem.

    If that is all good, the next cheapest is to replace the alternator. If that doesn't fix it, its possible that the VRM in the PCM is fried.
     

Share This Page