Detroit DD15 EPA07 (2007-09) Fault Code: SPN 171 FMI 2 (CPC) Ambient Temperature Sensor Data Erratic

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.