C.E. Niehoff & Co. N1224 Standard Troubleshooting Guides - Manual (Page 4)

Page 4
TG0045A
Section 3: J1939 Operation Modes
CAN/J1939 Interface
DESCRIPTION AND OPERATION
The CEN N3221, N3229, and N3232 digital regulators
are compatible with SAE J1939 communications stan-
dard for vehicle networking.
CEN uses MIL-STD connector MS3112E12-10P to inter-
face between the regulator and the vehicle J1939 data-
bus. Mating connector is MS3116E12-10S or equivalent.
If this connection is not used, it must be sealed with
connector cap and chain MS3181-12CA or equivalent-
supplied with all regulators. Connector pinout is shown
in Table 2. Message content is shown in Table 4.
Pin Identifi cation
TABLE 2 – J1939 Connector
Circuit Identifi cation
A
B
C
D
E
F
G
H
J
K
J1939+
J1939–
J1939/SHLD
Mfr use only
Mfr use only
Mfr use only
Mfr use only
unused
unused
unused
Figure 3 – J1939
Connector Pins
Notes:
Unused bytes broadcast as 0xff.
Contact C.E. NIehoff & Co. for definition of custom proprietary message content.
Regulator Readout Expected Reading
TABLE 3 – N3221/N3229/N3232 Regulator—J1939 Readout Diagnostics (see Table 4)
Alternator Output Voltage 28 V
Alternator Output Voltage 14 V
Alternator Speed
Regulator Temperature
Alternator Output
Charging System Hours 27–29 V
13.5–14.5 V
1200 to 8000 RPM
Less than 257 F/125ºC
0–100%
>0 hours
Action If Expected Reading Not Present
See Chart 1, page 6.
See Chart 1, page 6.
Check drive belt and charging system connections.
Decrease load on alternator.
Varies with load.
Check drive belt and charging system connections.
Table 4 — Message Data (Byte 1 Broadcast after Message ID)
PGN Name 1 2 3 4 5 6 7 8
FED5 Alt. Speed ALT RPM
FEF7 Alt. Voltage 24 V OUTPUT 12 V OUTPUT
FEA7 Temperature REG TEMP
FFC8 Proprietary
#1
ALT
LOAD
STATUS OVCO TRIP
COUNT
REG HOUR
METER
REG MINS
(0-59)