Alternator and charging system (Page 1/1)
Gogoman JUN 29, 04:24 PM
Ok so I have a 1987 GT V6

I put a new alternator and new battery. I’ve tested all of the fusible links and they’re all reading 12V I’ve been fixing some electrical gremlins that I found in trying to fix my battery not charging. I’ve ran a multi meter on the battery cold and running and I’m still at 12v or even 11v when run. I’ve went in the Orge Cave and read lots of information about this system.

Ask me anything questions I’ll answer as soon as I can. If I miss anything I’ll surly but in on this.

One more thing. I disconnected the female connector leading to the alternator, doing so I ran the vehicle and I started to get 13.50 V to the battery if this means anything and if I’m heading in the right direction, please let me know I’m leaning towards, but I’m not really sure take that with a grain of salt. Also, my instrument cluster light is not turning on even with this test the bolt has been changed with an existing bolt that does work.
theogre JUN 29, 06:07 PM
SI & CS Alt w/ "Fiero" V6 needs the Light working or simply won't turn On to charge anything.

If dash light won't work then put a test light to light pin on alt, other end to the battery +.
Any bulb ~ same watt/amp as 194 bulb will work. Do Not use LED to replace this bulb.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

Gogoman JUN 29, 08:52 PM

quote
Originally posted by theogre:

SI & CS Alt w/ "Fiero" V6 needs the Light working or simply won't turn On to charge anything.

If dash light won't work then put a test light to light pin on alt, other end to the battery +.
Any bulb ~ same watt/amp as 194 bulb will work. Do Not use LED to replace this bulb.





Alright I’ll run this test, also my dash doesn’t light up the brake light and my high-beams. Do you think that something wrong with my dash wiring could cause the alternator not to work. Maybe an open current stop the alternator??
Gogoman JUN 29, 09:50 PM
Ok I have realized that I actually own a 1 wire alternator this maybe explains why by disconnecting the female connection I was getting voltage ( further testing is needed)
theogre JUN 29, 10:21 PM
The dash back "board" glue fails then someone removes 1 or both plugs then bend the "pins."

Sometimes can short the "pins" too causing other problems.

see https://www.fiero.nl/forum/...HTML/138175.html#p18

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

Gogoman JUN 29, 10:41 PM
That actually happened to my original board. After I got a new board probably seems more evident. I’ll definitely be checking the pings for any damage. Also I’ll be getting all brand new 194 so I can rule that out.
jelly2m8 JUN 30, 05:37 AM

quote
Originally posted by Gogoman:
Alright I’ll run this test, also my dash doesn’t light up the brake light and my high-beams. Do you think that something wrong with my dash wiring could cause the alternator not to work. Maybe an open current stop the alternator??




No he is saying turn the damn key on, does the voltage light light? Gm in their infinite wisdom wired the charging circuit through the Instrument panel charge bulb.

[This message has been edited by jelly2m8 (edited 06-30-2024).]

theogre JUN 30, 09:18 AM

quote
Originally posted by jelly2m8:
No he is saying turn the damn key on, does the voltage light light? Gm in their infinite wisdom wired the charging circuit through the Instrument panel charge bulb.

Ford & many others to the same. Some models has a fix resistor or resistor wire in parallel w/ the bulb so when bulb fails, alt can turn on but that often doesn't help when have other wiring problems.

Later CS130 has second wire to turn on like 87+ Duke but 88 V6 skip that as well as any upgrade to CS skip that.