Detroit DD15 EPA10 (2010-13) Fault Code: SPN 171 FMI 4 (ACM) Typically Ambient Air Temperature Circuit Failed Low

NOTE: Please see the step by step troubleshooting procedures for this specific code.

PROBABLE CAUSES:
1. Ambient air temperature sensor not programmed correctly in ECM.
2. Ambient air temperature sensor connector/harness.
3. Ambient air temperature sensor.