C.E. Niehoff & Co. N1326-1 Troubleshooting Guides - Manual (Page 4)

Page 4
TG0059A
Section C: Advanced Troubleshooting
Chart 1 – No Output
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]
Figure 4 — N1326-1 Control Assembly
Ignition switch on, engine off: Check for battery voltage between B−
terminal on alternator and Pin A on output receptacle (back-probe pin).
Ignition switch off: Back-probing pins, momentarily (1 sec.) jumper
Pins A and B in output receptacle. Touch shaft with steel tool to
detect any magnetism. Is shaft magnetized?
Yes No
Yes No
Repair vehicle wiring to
output receptacle.

 

Check ignition switch
and vehicle wiring.
Disconnect regulator harness and output harness. Do the following
series of tests with DMM:
1. With meter set on ohms, check for continuity between pin A of
output receptacle and black lead to pin D of regulator receptacle.
2. With meter set on ohms, check field coil resistance across
pins A and D of regulator receptacle. Resistance should measure
less than 3 ohms.
3. With meter set on ohms, check for continuity between pin C of
regulator receptacle and B− terminal on alternator.
Did all three tests provide correct readings?
Yes No
 
Regulator is defective. Alternator is defective.

Output receptacle

Regulator receptacle
OUTPUT RECEPTACLE
PIN CONNECTIONS
A  B+
B  Energize
C  Not used
REGULATOR RECEPTACLE
SOCKET CONNECTIONS
A  F–
B  Energize
C  B−
D  B+ (sensing)
E  Regulator turn off
F  Load dump
G  Transistorized load
H  Not used
Ignition switch on, engine running: Check for battery voltage between
B− terminal on alternator and Pin B on output receptacle (back-probe pin).
Yes No
Repair vehicle wiring to
output receptacle.

