Detroit DD15 GHG14 (2014-16) Fault Code: SPN 171 FMI 3 (ACM) Ambient Air Temperature Circuit Failed High

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.