P0073
Ambient Air Temperature Sensor Circuit High Input
The car is reading the outside air temperature as too high or the sensor signal is out of range. This usually means the sensor, wiring, or connector has a problem. It can also happen if the sensor is damaged or unplugged.
- SEV
- 2/5
- DRIVE
- CAUTION
- DIY
- $15–$80
- SHOP
- $100–$250
Quick answer
AI-CITATION READYWhat it means
Can you drive with it?
Most common causes
- Faulty ambient air temperature sensor
- Loose, corroded, or damaged sensor connector
- Broken, rubbed-through, or open wiring in the sensor circuit
Typical repair cost
DIY usually runs $15–$80. Typical shop repair lands around $100–$250, depending on the root cause.
01 / Definition
P0073 is set when the engine control module sees a high voltage signal from the ambient air temperature sensor circuit. This typically means the circuit is open, the sensor is disconnected, or there is corrosion or damage in the wiring. In some vehicles, a faulty sensor reading can affect the display, HVAC behavior, or intake/engine management calculations.
02 / Drive status
With caution. You can usually keep driving, but the temperature display, climate control, or related engine strategy may be affected. Fix it soon, especially if other temperature-related warning lights appear.
03 / Symptoms
- Outside temperature reading is very high or shows --
- Check engine light
- Incorrect climate control behavior
- A/C or heater may act oddly on some vehicles
- Possible related temperature display problems
04 / Causes
| 1 | Faulty ambient air temperature sensor | high |
|---|---|---|
| 2 | Loose, corroded, or damaged sensor connector | high |
| 3 | Broken, rubbed-through, or open wiring in the sensor circuit | high |
| 4 | Sensor mounted in a damaged location or exposed to impact | medium |
| 5 | PCM/ECM issue or reference voltage problem | low |
05 / Diagnostic sequence
- 01Check the outside temperature reading on the dashboard for an unrealistic high value.
- 02Inspect the ambient air temperature sensor location, usually near the front bumper, grille, mirror, or radiator support.
- 03Unplug and inspect the connector for corrosion, bent pins, water intrusion, or loose fit.
- 04Inspect wiring for cuts, chafing, broken insulation, or a wire pulled open near the front of the vehicle.
- 05Measure sensor resistance or voltage using the service manual specifications.
- 06Compare the sensor reading with ambient conditions and test wiring continuity to the PCM if needed.
- 07Replace the sensor if it is out of specification, then clear codes and verify the repair.
06 / Repairs
| 1 | Repair loose or damaged connector pins and clean corrosion from the sensor connector | $15–$60 |
|---|---|---|
| 2 | Repair broken or open wiring in the ambient temperature sensor circuit | $50–$150 |
| 3 | Replace the ambient air temperature sensor | $20–$80 |
| 4 | Diagnose and repair PCM or harness faults if the circuit tests good | $150–$400 |
07 / Related codes
08 / FAQ
What does P0073 mean on a car?
It means the ambient air temperature sensor circuit has a high input signal, usually from an open circuit, bad sensor, or wiring problem.
Where is the ambient air temperature sensor located?
It is often mounted behind the front grille, near the radiator support, in the front bumper area, or sometimes in a side mirror.
Will P0073 affect how the car runs?
Usually it mainly affects the outside temperature reading and some climate control functions, but it should still be repaired because the signal is not correct.
Can I clear P0073 without fixing it?
You can clear it temporarily, but it will likely return if the sensor or wiring problem is still present.
09 / Source and method
- DATA BASIS
- OBD-II REFERENCE + OBD2.HELP
- METHOD
- STATIC VALIDATION
- SAFETY
- INFORMATIONAL
This page combines OBD-II diagnostic reference data with OBD2.help generated diagnostic guidance for code meaning, likely causes, and repair direction.
Publishing uses deterministic schema and build validation, plus manual spot checks on representative pages before release.
Safety-critical diagnosis and repairs should be confirmed with a qualified mechanic, especially when the vehicle is misfiring, overheating, or losing power.