FRAMING JOHN DELOREAN - ON VOD www.framingjohndeloreanfilm.com
Page 2 of 3 FirstFirst 1 2 3 LastLast
Results 11 to 20 of 21

Thread: Alternator not charging

  1. #11
    Senior Member
    Join Date:  May 2011

    Location:  Northern NJ

    Posts:    8,579

    My VIN:    10757 1st place Concourse 1998

    If you don't change to LED (and IMHO it isn't necessary) at least replace all the bulbs so you don't have to take the binnacle out again anytime soon.
    David Teitelbaum

  2. #12
    Member
    Join Date:  Sep 2019

    Posts:    90

    Quote Originally Posted by David T View Post
    If you don't change to LED (and IMHO it isn't necessary) at least replace all the bulbs so you don't have to take the binnacle out again anytime soon.
    I was wondering about changing to LED, I will just replace the bulbs and put it back in, thanks.

  3. #13
    Member
    Join Date:  Sep 2019

    Posts:    90

    Quote Originally Posted by northeast dmc View Post
    I was wondering about changing to LED, I will just replace the bulbs and put it back in, thanks.
    Regarding the alternator not charging, I went back in to make sure I had the correct bulb as the ones I had on hand where for the door lights, differnt part number, so I stopped and bought the 161 put it in and the battery light still comes on and no charging. Is there any thing else I can check that might cause the alternator to not charge? I have had a couple of brief indications of charging but that is all.

  4. #14
    Senior Member
    Join Date:  Nov 2014

    Location:  Northwest Florida

    Posts:    324

    My VIN:    Midproduction

    No that you have the correct bulb in the dash - put the key on Run (without starting engine) and test the brown/yellow wire going to the alternator with a multimeter - you should be getting 12V.



    Quote Originally Posted by northeast dmc View Post
    Regarding the alternator not charging, I went back in to make sure I had the correct bulb as the ones I had on hand where for the door lights, differnt part number, so I stopped and bought the 161 put it in and the battery light still comes on and no charging. Is there any thing else I can check that might cause the alternator to not charge? I have had a couple of brief indications of charging but that is all.

  5. #15
    Senior Member
    Join Date:  May 2011

    Location:  Northern NJ

    Posts:    8,579

    My VIN:    10757 1st place Concourse 1998

    If the belt is spinning the alternator and the light is on, it's time to take the alternator to a shop to get it rebuilt.
    David Teitelbaum

  6. #16
    Member
    Join Date:  Sep 2019

    Posts:    90

    Quote Originally Posted by dmcnc View Post
    No that you have the correct bulb in the dash - put the key on Run (without starting engine) and test the brown/yellow wire going to the alternator with a multimeter - you should be getting 12V.
    The alternator is/was new when I put the motor in, I checked the voltage at the brown /yellow wire with key on,not running and with the wire connected to the alternator I read about 1.2 volts, I unhook the wire form the alternator and it goes to what the battery voltage is at, 12 volts plus minus depending on how long since I charged it. I do seem to have something drawing juice when the car is off. I am going to disconnect the battery tonight to see if battery holds charge or if the battery is bad. Brand new a month ago.

  7. #17
    Administrator Ron's Avatar
    Join Date:  Jun 2011

    Location:  North GA

    Posts:    6,176

    Club(s):   (SEDOC) (DCUK)

    If the battery is bad, but good enough to start the engine after a charge, the light should still go out and the alternator should raise it to 13.5V or more. So, I'm with David -- Pull the alternator and get it tested/repaired.

  8. #18
    Member
    Join Date:  Sep 2019

    Posts:    90

    Quote Originally Posted by Ron View Post
    +1

    The large brown wires go on the main terminal. They have 12V at all times.
    The small brown wire with a yellow tracer/stripe goes to the terminal marked "L" (Light) or "F" (Field). It has 12V when the key is in the "Run" position.
    The small solid brown wire goes to the remaining terminal on original units. It has 12V when the key is in the "Run" position. It is usually not needed on rebuilt or replacement units...
    Most auto parts can test the unit if you pull it off (FREE).
    Well back to the alternator again. Well pulled it out and decided to try it on the bench, put it the vise, hooked the multi meter up to the out put post and ground to the vise. Took my portable battery jumper hooked up ground to the vise, and with a nail in the positive applied to the differnet terminals in the plug in area. (there are 4 prongs) no description on the alternator for the prongs. And with me turning the pulley with a impact would find the terminal that would "engage" the alternator and put out around 14 volts. Install in car and nothing.

  9. #19
    Administrator Ron's Avatar
    Join Date:  Jun 2011

    Location:  North GA

    Posts:    6,176

    Club(s):   (SEDOC) (DCUK)

    Quote Originally Posted by northeast dmc View Post
    Well back to the alternator again. Well pulled it out and decided to try it on the bench, put it the vise, hooked the multi meter up to the out put post and ground to the vise. Took my portable battery jumper hooked up ground to the vise, and with a nail in the positive applied to the differnet terminals in the plug in area. (there are 4 prongs) no description on the alternator for the prongs. And with me turning the pulley with a impact would find the terminal that would "engage" the alternator and put out around 14 volts. Install in car and nothing.
    Assuming you also put the battery jumper's positive wire on the main alternator terminal since it put out... If so, it should work on the car if your small brown with yellow trace wire measures 12V (disconnected) and you put it on the same terminal that you put the nail on to make it output ~14V. (The others in the socket are not needed.)
    Be careful -- Those regulators are not very forgiving if you apply ground or power to the wrong one...

    Are auto parts tests unavailable there?

    Post a pic or two of the alternator?

  10. #20
    Senior Member
    Join Date:  May 2011

    Location:  Northern NJ

    Posts:    8,579

    My VIN:    10757 1st place Concourse 1998

    Not really a definitive way to bench test the alternator. You really should put a load on it. You could have bad diodes or a faulty regulator. If the alternator does test good you could have a wiring problem and/or a bad battery. Get the alternator properly bench tested and have the battery checked. If they are both good you have a wiring problem in the car.
    David Teitelbaum

Page 2 of 3 FirstFirst 1 2 3 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •