Lofa CANplus 640c, Руководство по эксплуатации, Страница: 32 / 34

6. Miscellaneous
Possible Cause Possible Remedy
Configuration file does not match firmware ver-
sion Reload configuration file from the config pro-
gram with matching version
6.4.1 Testing a Warning or Shutdown
Shutdown simulation with ECU controlled engines requires using the ECU diagnostic tool. Refer to
the diagnostic tool documentation to simulate a warning or shutdown.
6.4.2 Testing CAN
Most information provided to the CANplus
®
display is sent by the ECU via the CAN bus. CAN is
an international data bus used to support SAE J1939. If this connection is broken or improperly
terminated, the CANplus
®
display cannot show ECU parameters such as engine hours, oil pressure
and diagnostic codes. This test procedure helps identify the problem location.
1. Disconnect the battery.
2. Identify the engine diagnostic plug. Connect an ohmmeter across the CAN pins of the diagnostic
plug.
3. A reading of 60±5 Ω indicates both ends of the bus are correctly terminated and the bus is intact.
4. A reading of 120±10 Ω indicates only one end of the bus is terminated. (Note: The CP640c has
switchable termination via software. Please see CAN bus settings in the Tech menus for more
information.)
An ohmmeter reading of around 120 Ω indicates the bus to the terminator in the panel is complete
and the problem is between the panel and the engine terminator.
An open circuit ohmmeter reading indicates the bus to the engine terminator is complete and
the problem is between the panel and the diagnostic plug.
5. Reinstall the terminator resistor and reconnect the battery.
If the ECU diagnostic tool is available, use it to verify the ECU is transmitting CAN data. Refer to
ECU documentation to identify and correct the error.
If another panel is available for testing, replace the panel to determine if the error is in the panel.
6.5 Diagnostic Trouble Codes (DTC)
CAN Diagnostic Trouble Codes are a pair of numbers; the SPN and FMI. The SPN indicates the
faulting subsystem and the FMI identifies the type of failure.
6.5.1 Typical SPNs
Standard SPN codes are defined by SAE J1939-71. Not all standard codes are provided by ECUs.
Manufacturers may add additional SPN codes beyond the codes identified in J1939-71. Refer to
ECU documentation for supported SPNs. Table
2 on the next page describes some example SPNs.
6.5.2 FMI
FMI codes are defined by SAE J1939-71. Refer to ECU documentation for correct interpretation of
FMI codes for a specific SPN. Table
3 on page 29 describes each FMI.
LOFA document No. 463-3002-22 Page 27