C.E. Niehoff & Co. C653/C653A/C625 Troubleshooting Guides - Manual (Page 6)

Page 6 TG13G
A2-214 Regulator
DESCRIPTION AND OPERATION
A2-214 regulator is either attached directly to the outside
of alternator or remote-mounted.
Main diagnostic feature of regulator is a green lens LED
located on the front of the regulator. LED indicates
whether regulator has been energized. See Table 2 for
LED indication and status.
Regulators with OVCO (overvoltage cutout) will trip at
vehicle electrical system voltages above 32 volts that
exist longer than 3 seconds. OVCO feature detects high
voltage and reacts by signaling the F+ alternator circuit
to open. This turns off alternator. Restarting engine
resets OVCO circuit. Regulator regains control of alter-
nator output voltage.
TROUBLESHOOTING
Shut down vehicle and restart engine. If alternator func-
tions normally after restart, a “no output condition” was
normal response of voltage regulator to “high voltage”
condition. Inspect condition of electrical system, includ-
ing loose battery cables, both positive and negative. If
battery disconnects from system, it could cause “high
voltage” condition in electrical system, causing OVCO
circuit to trip.
If you have reset alternator once and electrical system
returns to normal charge voltage condition, there may
have been a one time, high voltage spike, causing OVCO
circuit to trip.
If OVCO circuit repeats cutout a second time in short
succession and shuts off alternator F+ circuit, try third
restart. If OVCO circuit repeats cutout, go to page 8.
REMOTE-MOUNTED REGULATORS: CHECK
CONDITION OF FUSE IN WIRING HARNESS
BEFORE TROUBLESHOOTING TABLE 2—A2-214 Regulator
LED Indications and Status
INDICATION STATUS
ON steady Normal regulator operation.
Alternator is producing output.
FLASHING Regulator is receiving energize
signal. LED will flash until
alternator produces output.
OFF Regulator is not receiving ener-
gize signal or OVCO has tripped.
Section D: A2-214 Advanced Troubleshooting