97 Nissan Battery not charging

[NissanPU]

1997 Pickup has new battery, alternator, and starter. All test fine on bench. In vehicle the alternator only charges 12.8-13.8 amps. On bench test at 3 different shops the alternator measures 14.8 volts and 65 amps output. I'm a novice using test meters.
Belt is fine, connectors are in perfect condition, ground is good, fusible links have continuity. Is there a relay or fuse or something else that is keeping alternator from fully charging battery?
Thanks.
November 7, 2016

[whomadewho]

Welcome to the site. This site offers a variety of sites including service manuals. 12.8 - 13.8 indicates the charging system is working excellent. A constant 14.8 voltage would be considered an overcharge and would shorten the life of the battery in a short period of time. When a bench test Is performed the regulator is being bypassed which results in the 14.8 reading. There are high output alternators on the market, but the 65 amp. Alternator will work fine.

[NissanPU]

Good information. However the alternator is not charging the battery. Has anybody else experienced this? Thanks

[NissanPU]

I removed wires and plugs from positive battery post. Cleaned them well and applied dielectric grease. Then reinstalled all making certain of full contact. Cleaned posts and cable clamps well. Applied grease again. Tightened well and now the alternator charges at 14.45 volts. With emergency-flashers on, high-beam headlights on, and air conditioner fan on high, then the volts reduced to 14.04. When these were turned off, the voltage returned to 14.4. Before this repair, the alternator was charging as low as 13.5 volts, I wrongly wrote 13.8 volts when I first posted this issue.
Apparently the problem was caused by poor electrical connections when new battery was installed by A-Autoparts Store. Thanks for help.