This 1994 full sized Dodge pickup came in with a complaint of the battery going dead. A quick check showed a no charge condition. With the engine running, I checked for power on the main alternator power lead. Next I checked for power going to the field terminals. The inside one had power but the outer terminal did not, as shown in the picture below. Diagnosis of an open field circuit within the alternator. Most likely worn brushes.
Time to disconnect then battery. Then, I loosened and removed the belt from the alternator.
Loosened and removed the upper and lower mounting bolts. Rolled the alternator slightly forward to disconnect all wiring connections.
After sliding the alternator off of the lower mount, I rolled the alternator slightly forward to disconnect all wiring connections. Next, I started rotating the alternator ccw around the dipstick tube.
I continued rotating the alternator around the tube and under the a/c lines.
After repairing the alternator, I tested the field circuits again. To view the repair of this alternator please click here. This time I had a flickering light on the outer field terminal. Sorry you can’t see the flickering in a still shot.
You can however see that the charging system is now working.