C.E. Niehoff & Co. N1450 Troubleshooting Guides - Manual (Page 5)

Page 5
TG57B
Section C: Advanced Troubleshooting
(CONT’D)
Figure 3 – Alternator-to-Regulator
Harness Plug
Yes No
Alternator is defective.
Unplug alternator-to-regulator harness from regulator. Connect red lead from DMM to pin J in plug.
Connect black lead to pin K in plug. Does resistance read 5-6 ohms?
Chart 2 – No Alternator Output – Test OVCO Circuit
Yes No
Replace existing regulator with known good regulator.
Run engine. Does OVCO trip?
Alternator is defective. Original regulator is
defective.
 
Yes No
With red lead from DMM connected to pin K in plug, connect black lead to B– terminal. Does
resistance read OL (out of limits)?
Alternator is defective.




If you have questions about your alternator or any of these test procedures, or if you need to locate a Factory Authorized Service Dealer, please contact us at:
C. E. Niehoff & Co.• 2021 Lee Street • Evanston, IL 60202 USA
TEL: 800.643.4633 USA and Canada • TEL: 847.866.6030 outside USA and Canada • FAX: 847.492.1242
E-mail us at [email protected]
ALTERNATOR CONNECTOR
PIN CONNECTIONS
A  AC 1 G  T+ 1
B  AC 2 H  T– 1
C  Not used J  F+
D  Not used K  F–
E  B+ 2 L  B+ 1
F  Not used M  B–
B+ 1 primary
(high load)
output terminal.
Battery must be
connected to this
terminal for unit
to be energized.

B+ 2
secondary
(low load) output
terminal

B– terminal
