User manual

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2.11 CAN (J1939)
Menu Location
Page
1
J1939
Advanced Setup > J1939 Setup
63
2
Engine Speed
Advanced Setup >Speed Sensing > Signal
Source + Warning and/or Failure
55
3
High Engine
Temperature
Advanced Setup > High Engine Tmp > Signal
Source+ Warning and/or Failure
50
4
Oil Pressure
Advanced Setup > Oil Pressure > Signal
Source+ Warning and/or Failure
5
Oil Level
Advanced Setup > Oil Level > Signal Source
6
Low Engine
Temperature
Advanced Setup > Low Engine Temp > Signal
Source+ Warning and/or Failure
Wiring
Dynagen’s wiring harness can be used for runs of 5ft or less. Otherwise a proper
120Ohm impedance twisted pair should be used. Also consider shielding if the
application warrants it.
ECM Power
The GSC400 fuel relay output is usually used to power the ECM. The fuel relay
turns on at the start of preheat (even if no output is set to preheat). If the preheat
time is set to zero the fuel output turns on during the start of cranking.
The ECM usually must be given time to boot-up to allow it to detect the cranking
of the engine.
Bus Termination
The CAN communication bus’s CANL and CANH lines must be terminated
with two 120Ohm, 0.5 Watt resistors, one on each end of the bus. If you are
not connecting to an existing bus you must do this. If you are connecting to an
existing bus check that it has the proper terminating resistors.
To check for proper resistance disconnect the CAN bus harness from the
GSC400 and measure across the CANH and CANL pins on the harness
connector. It should be 60 Ohms (two 120 Ohms in parallel). If you measure
120Ohms then only one resistor has been installed.
U
If using the optional J1939 harness DWG1373R3-5 from Dynagen there is a
120Ohm resistor built in. It can be cut out if the GSC400 is not the last device on
the bus. If you are using DWG1375R2-5 this version of the J1939 harness does
not have a terminating resistor.