Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2018 Ford Fiesta STFACTORY OEM SERVICE PROCEDURE
DTC P00AC - Intake Air Temperature Sensor 1 Circuit Low (Bank 2)
P00AC - INTAKE AIR TEMPERATURE SENSOR 1 CIRCUIT LOW (BANK 2)
| Description: | This DTC sets when the intake air temperature bank 2, sensor 1 (IAT21) sensor signal is less than the self-test minimum. | ||
| Possible Causes: |
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| Diagnostic Aids: | An IAT21 sensor PID reading less than the self-test minimum with ignition ON engine OFF or during any engine operating mode indicates a concern is present. | ||
| Application | Key On Engine Off | Key On Engine Running | Continuous Memory |
| All | GO to PINPOINT TEST DA . | ||
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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