This is what alldata says about P0071 (P0074 is not listed for the 500 pop)
P0071-00-AMBIENT AIR TEMPERATURE SENSOR PERFORMANCE
Following a start to run delay time, the outputs of the ambient, engine coolant and intake air temperature sensors are compared. If the engine coolant and intake air temperature sensors agree and the ambient air temperature does not agree, the ambient air temperature sensor is declared as irrational. If declared irrational a second comparison will be done after a short drive cycle.
- When Monitored:
Engine off time is greater than 480 minutes and the vehicle has been driven for one minute over 35 mph. Ambient temperature is greater than -64° C (-83° F).
- Set Condition:
The PCM compares the ambient, engine coolant and intake air temperature sensor values. If engine coolant and intake air temperature sensors agree with each other but ambient air temperature does not agree, the ambient air temperature sensor is declared as irrational. Two Trip Fault. Three good trips to turn off the MIL.
Diagnostic Test
ACTIVE DTC
NOTE: Diagnose any CAN - Communication DTCs in the PCM and any Ambient Air Temperature Sensor DTCs in the BCM before continuing.
1. Turn the ignition off.
2. If possible, allow the vehicle to sit with the ignition off for more than 480 minutes in an environment where the temperature is consistent and above -7°C (19.4°F).
3. Test drive the vehicle. The vehicle must exceed 48 km/h (30 mph) during the test drive. Do not cycle the ignition off when the test drive is completed.
4. With the scan tool, select View DTCs.
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I had the same codes AFTER replacing the sensor.
AND
I cleared the codes INSTEAD of drive cycling as stated above and the code never came back.
So if you don't have the ability to clear the codes you need to drive cycle (test drive) the vehicle.
Link to the sensor that I purchased to repair my 500 ambient air temperature sensor in the United States.
https://www.ebay.com/itm/234909728293
