SPN 111 is a diagnostic trouble code for Engine Coolant Level.
FMI 1 – Data Valid But Below Normal Operational Range – Most Severe
FMI 3 – Voltage Above Normal Or Shorted To High Source
FMI 4 – Voltage Below Normal Or Shorted To Low Source
FMI 17 – Data Valid But Below Normal Operating Range – Least Severe Level
FMI 18 -Data Valid But Below Normal Operating Range – Moderately Severe level
Troubleshoot:
Coolant level, sensor, ECM