C.E. Niehoff & Co. C802/C802D/C820 Troubleshooting Guides User Manual
Page 6

Page 6
TG0004E
Section 3: Advanced Troubleshooting
Chart 1 –
C802 – No Air-Conditioning/NO ALT OUTPUT Light On
(CONT’D)
Yes
No
Connect DMM red lead to D+ (or P) terminal on regulator. Connect black lead
to alternator B– terminal.
At D+ terminal – is regulator setpoint voltage present?
At P terminal – is 12 V to 18 V present?
Stop engine. Alternator is good.
Check vehicle wiring.
Yes
No
Stop engine. Unplug alternator-to-regulator harness. Set DMM to Diode Test.
Connect DMM red lead to socket D on alternator-to-regulator harness plug.
Connect red lead to alternator B+ terminal. Does continuity exist?
Regulator is defective.
Go to Chart 3, page 8.
T
T
T
T
T
Yes
No
With engine running, verify operation of charging system. Is regulator setpoint voltage present?
T
Go to Chart 2, page 7.
Figure 5 – Alternator-to-Regulator Harness Plug
SOCKET CONNECTIONS
Socket A B–
Socket B Field +
Socket C Field –
Socket D AC
Socket E B+