SPN 639 FMI [9,13] is a diagnostic trouble code for J1939 Network #1, Primary Vehicle Network
FMI 2 – Data Erratic
FMI 8 – Abnormal Frequency
FMI 9 – Abnormal Update Rate
FMI 13 – Out Of Calibration
FMI 19 – ECU internal fail
Troubleshoot:
ECM connections, fuses, wiring harness
