SPN 523/FMI 9
This fault is typically the J1939 ETC2 message is missing.
Check as follows:
- Check for multiple codes:
- If CPC SPN 168/FMI 0/14/18 (Battery Voltage) are present troubleshoot these first.
- If MCM SPN 625/FMI 9 is present, troubleshoot and repair the CAN line.
- If only a “J1939 Error” fault is present, go to the next step.
- Has the CPC been recently reprogrammed?
- If yes, check the proper configuration of the CPC.
- If no, connect ServiceLink to determine which modules are configured for the vehicle and their communication status. Once this is done, follow the appropriate module communication troubleshooting procedures for the affected module.