C.E. Niehoff & Co. N1224 Troubleshooting Guides - Manual

TG0058A
Page 1 of 1
N1224-1 Alternator w/ N3221 Regulator
Quick Troubleshooting
C. E. Niehoff & Co. • 2021 Lee Street • Evanston, IL 60202 Tech Services Hotline 800-643-4633
Figure 1 — N1224 Wiring Diagram
Basic Troubleshooting
1. Inspect charging system components
Check connections at ground cables, positive
cables, and regulator harness. Repair or replace
any damaged component before troubleshooting.
2. Inspect connections of vehicle batteries
Connections must be clean and tight.
3. Determine battery type, voltage, and state
of charge
Batteries must be all the same type for system
operation. If batteries are discharged, recharge
or replace batteries as necessary. Electrical
system cannot be properly tested unless batter-
ies are charged 95% or higher.
CAUTION
T
Yes
Turn off engine, leave key on. Disconnect alternator-
to-regulator harness plug. Connect jumper wire
from pin A in plug to B+ terminal on alternator.
Spark will occur. Touch steel tool to shaft to detect
significant magnetism. is shaft magnetized?
No
Alternator is defective.
T
When performing the following
test, connect jumper wire away
from pin A or not at pin A.
Spark may erode pin.
CAUTION
Remove jumper wire. Reconnect harness to regulator and make sure connection is tight. Operate vehicle.
Observe charge voltage.
If charge voltage is above 33 volts, immediately shut down system. Electrical system damage may
occur if charging system is allowed to operate at excessive voltage.
If voltage is at or below regulator setpoint, let charging system operate for several minutes to normalize
operating temperature.
If voltage continues to be above or below setpoint, remove and replace regulator. Retest charging system.