80.1 SPN 986/FMI 9
This fault is typically the J1939 CM1 message is missing.
80.1.1
Missing J1939 CM1 Message Check
Check as follows:
1. Check for multiple codes:
[a] If CPC SPN 168/FMI 0/14/18 (Battery Voltage) are present troubleshoot these first.
[b] If MCM SPN 625/FMI 9 is present, troubleshoot and repair the CAN line.
[c] If only a “J1939 Error” fault is present, go to step 2.
2. Has the CPC been recently reprogrammed?
[a] If yes, check the proper configuration of the CPC.
[b] 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.
