Battery Light On

Joe83

Registered User
Joined
Oct 7, 2015
Posts
38
Reaction score
0
Location
Mayflower, AR
Battery light came on yesterday.
Checked alternator, was not charging.
Had it tested and it tested good.
The alternator has one heavy wire and one plug with 2 wires.
In the plug one wire was corroded, I replaced the plug, now it is charging but the light is still on.

Each wire in the plug is neither hot nor ground.
In the fuse box under the hood,
The mini fuses, right side, 1,3,9,11 have no power, 5,7 are not used.

Any help would be appreciated!

1999 F350 "early" crew cab, long bed, non dually. 240,000 miles.



Sent from my iPhone using Tapatalk
 

Joe83

Registered User
Joined
Oct 7, 2015
Posts
38
Reaction score
0
Location
Mayflower, AR
I can run a jumper from the battery to either of the 2 small wire that are in the plug that plugs into the alternator and the light goes out.

Thanks


Sent from my iPhone using Tapatalk
 

Joe83

Registered User
Joined
Oct 7, 2015
Posts
38
Reaction score
0
Location
Mayflower, AR
Ok, fuses that have no power are for the lights, they work with lights on, scratch that.

If I unplug the plug on the alternator, the light goes out but it does not charge, when I plug it up it charges, but the battery light comes on.


Sent from my iPhone using Tapatalk
 

79jasper

Chickenhawk
Joined
Oct 13, 2012
Posts
17,367
Reaction score
1,930
Location
Collinsville, Oklahoma
What was the test procedure on the alt?
Even though it may have tested "good," it's probably on its way out.

Sent from my SAMSUNG-SM-G890A using Tapatalk
 

OLDBULL8

Good Morning Ya'll.
Supporting Member
Joined
Feb 12, 2009
Posts
9,923
Reaction score
338
Location
Delphos , Ohio
Check the 5 amp fuse #29 in junction box in the cab under the dash. Edited.
 
Last edited:

OLDBULL8

Good Morning Ya'll.
Supporting Member
Joined
Feb 12, 2009
Posts
9,923
Reaction score
338
Location
Delphos , Ohio
Here's your circuit.
 

Attachments

  • image0.jpg
    image0.jpg
    990 KB · Views: 17
  • image0-001.jpg
    image0-001.jpg
    983.9 KB · Views: 15
  • image0-002.jpg
    image0-002.jpg
    1,019.8 KB · Views: 14

Joe83

Registered User
Joined
Oct 7, 2015
Posts
38
Reaction score
0
Location
Mayflower, AR
Thanks Bull, I called my self checking them all, I will check again.


Sent from my iPhone using Tapatalk
 

Joe83

Registered User
Joined
Oct 7, 2015
Posts
38
Reaction score
0
Location
Mayflower, AR
Now, on that diagram, it shows one light green/red wire going through the lamp and to the fuse.
Where does the other one go?
There is 2 in the plug.


Sent from my iPhone using Tapatalk
 

OLDBULL8

Good Morning Ya'll.
Supporting Member
Joined
Feb 12, 2009
Posts
9,923
Reaction score
338
Location
Delphos , Ohio
Here is another circuit diagram, all the circuits I show are from the factory 99 wiring diagrams. Have no idea of what they mean by GIVEAWAY.

The second pic is of a 3G Alt. maybe you can figure it out from that.
 

Attachments

  • image0.jpg
    image0.jpg
    1,003.1 KB · Views: 14
  • post-889-0-41043700-1324555726.jpg
    post-889-0-41043700-1324555726.jpg
    66.7 KB · Views: 12

79jasper

Chickenhawk
Joined
Oct 13, 2012
Posts
17,367
Reaction score
1,930
Location
Collinsville, Oklahoma
They can show up fine depending on the tester used. Try orielly for a second check.
Do you have a voltmeter to check actual output?

Sent from my SAMSUNG-SM-G890A using Tapatalk
 

OLDBULL8

Good Morning Ya'll.
Supporting Member
Joined
Feb 12, 2009
Posts
9,923
Reaction score
338
Location
Delphos , Ohio
The trouble with stores checking the Alt is, they put 12.5 VDC to the field circuit A, that gives the Alt full output ~14.7 VDC or more and call it good.
 

79jasper

Chickenhawk
Joined
Oct 13, 2012
Posts
17,367
Reaction score
1,930
Location
Collinsville, Oklahoma
^ that's what I mean by different stores. Some have better machines.
Bill, have you ever heard of using a battery load tester to test a alt?

Sent from my SAMSUNG-SM-G890A using Tapatalk
 

Joe83

Registered User
Joined
Oct 7, 2015
Posts
38
Reaction score
0
Location
Mayflower, AR
Used O'Reilly and autozone with 2 used alternators, one knock off, one motor craft.

Both outputs 14.2-14.5 per my Fluke multimeter. Light still on.


Sent from my iPhone using Tapatalk
 

Joe83

Registered User
Joined
Oct 7, 2015
Posts
38
Reaction score
0
Location
Mayflower, AR
I have 0 voltage on either of the wires in the 2 wire plug.


Sent from my iPhone using Tapatalk
 
Top