C.E. Niehoff & Co. N1601/N1602/N1603/N1604 Troubleshooting Guides - Manual (Page 9)

Page 9 TG29D
Section C: Advanced Troubleshooting
(CONT’D)
Test for battery voltage across and diagonally between both alternator B+ terminals and alternator B-
terminals. Does battery voltage exist?
Repair vehicle wiring as necessary. Continue test.
Yes No
Chart 4 – N1604-all models – No Output


Connect DMM across socket D and socket C in
harness plug. Does battery voltage exist?
Yes No
Alternator is defective.

Using diode tester, attach red lead to alternator
anti-drive end B– terminal and black lead to
socket B in harness. Continuity should exist.
Reverse leads. No continuity should exist.
Yes No
Alternator is defective.
 
Yes No
Repair vehicle circuit to IGN terminal.
Vehicle charging circuit test is complete.

Regulator is defective.

Yes No
Alternator is defective.


Figure 9 – Alternator-to-Regulator Harness Plug
SOCKET CONNECTIONS
Pin A F–
Pin B AC Terminal
Pin C B–
Pin D B+
Install a jumper from anti-drive end B+ terminal on alternator to IGN terminal on regulator. Touch shaft with steel
tool to detect significant magnetism. Is shaft magnetized?

Unplug alternator-to-regulator wiring harness.
Install a jumper from socket A in harness plug
to anti-drive end B– terminal on alternator.
Touch shaft with steel tool to detect significant
magnetism. Is shaft magnetized?
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