Question

What is code P0073?

P0073 code is defined as “Ambient Air Temperature Circuit High,” indicating an issue with the Ambient Air Temperature sensor circuit, i.e., it is experiencing a high input. When the code logs, you can assume that the sensor, its electrical connection, or wiring is damaged.

The automatic climate control systems help us choose the right temperature for our car’s cabin. Ideally, the Climate Control Module (CCM) regulates the climate control system. To operate correctly, the CCL depends on many sensors that monitor the various aspects that impact cabin climate.

The Ambient Air Temperature (AAT) sensor measures the temperature outside your car. The sensors convert the temperature information into an electric signal and transmit it to the powertrain control module (PCM). The PCM also shares this information with other modules. The devices use this information to regulate functions on the dashboard, such as the automatic climate control process and the ambient temperature display. The PCM logs this error code when it observes the AAT’s signal is higher than the expected range.

What are the symptoms of the P0073 code?

These are some common signs of the P0073 engine code:

• The check engine light illuminates
• Defective climate control functions
• The instrument cluster won’t read outside temperature correctly
• The overhead console won’t read outside temperature correctly
• Hard engine start
• Improper functioning of the AC

What is the cause of the code P0073?

These are the various reasons why this error code shows up in your car:

• Defective Ambient Air Temperature (AAT) sensor
• Issues with the AAT sensor circuit, like defective wiring or poor connections
• Problems with the control module
• The electric connector or circuitry is corroded
• The ambient air temperature harness is broken or is short
• The sensor is covered by debris
• In rare circumstances, a defective powertrain control module

How to fix the P0073 code​

Ideally, to fix this error code, you must check the sensor, its wiring, and its connector for defects or poor connections and change the Ambient Air Temperature (AAT) sensor or wiring if needed. Then follow these steps:

• After making the required repairs, clear the code using an OBD-II scan tool to check whether the code reappears.
• Find the AAT sensor. Check the sensor for any damage, like rust or cracks. Use a multimeter to measure the AAT sensor’s resistance. If the resistance is greater than the expected range for the existing ambient temperature, the sensor may be defective.
• Then, inspect the wiring harness and connector for any damage. Use a multimeter to inspect the wiring harness and the connector’s continuity. Examine for short circuits in the wiring harness and connector.
• Inspect the sensor wire’s voltage. If it is close to 5V, connect the sensor and recheck the voltage. If the voltage is right, but the code remains, the problem is probably in the wiring between the AAT sensor and the PCM.
• If the AAT sensor is defective, replace it. Repair or change the wiring or connector if damaged.

Can I drive with a P0073 code?

Yes, technically, you can drive with code P0073 if that’s the only error code that the powertrain control module has logged. However, we recommend that you quickly take your car to a qualified technician to get it repaired to ensure optimal performance and possibly avoid issues in the future.

How much does it cost to fix the P0073 code?

Fixing this error code can cost you between $10 and $100 for the sensor and $50 and $100 as labor costs. However, the exact cost may differ based on your car and the area in which you live.