C.E. Niehoff & Co. N1233 Troubleshooting Guides - Manual (Page 5)

Page 5
TG0021A
Section 3: Advanced Troubleshooting
Yes No
Alternator is defective.
With engine off, unplug alternator-to-regulator harness. Connect DMM red lead to pin A on harness plug.
Connect black lead to pin F on same plug. Does resistance measure about 1.2 (± 0.2) ohms?
Chart 2 – No Alternator Output – Test OVCO Circuit
Yes No
Connect DMM red lead to pin A on alternator-to-
regulator harness plug. Connect black lead to
alternator B– terminal. Does continuity exist?
Regulator is defective.
Alternator is defective.
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Figure 4 – Alternator-to-Regulator Harness Plug
PIN CONNECTIONS
Pin A F–
Pin B Phase
Pin C B–
Pin D B+
Pin E D+
Pin F F+
(CONT’D)