Detroit DD15 GHG14 (2014-16) Fault Code: SPN 188 FMI 31 (MCM) Idle Speed is Higher Than Targeted Idle Speed

DESCRIPTION:
Idle speed out of range.

MONITORED PARAMETER:
Engine rpm

TYPICAL ENABLING CONDITIONS:
Engine rpm = idle.

MONITOR SEQUENCE:
None

EXECUTION FREQUENCY:
Continuous when enabling conditions met.

TYPICAL DURATION:
10 seconds

DASH LAMPS:
MIL

VERIFICATION:
Engine Idle: One minute.

PROBABLE CAUSES:
1. If any camshaft or crankshaft codes, fix those first.
2. If any throttle or idle validation switch codes, fix those next.
3. Injector failure.