B1252 – Air Temperature Internal Sensor Circuit Short To Battery
The ODBII code B1252 indicates a short circuit in the air temperature internal sensor circuit, causing it to connect directly to the battery voltage, which can lead to incorrect readings or sensor failure.
The severity of ODBII code B1252 is moderate.
Common Causes For: B1251 Air Temperature Internal Sensor Circuit Open
- Shorted wiring or connectors
- Faulty air temperature sensor
- Corroded or damaged electrical connections
- Malfunctioning engine control module (ECM)
- Improper installation or replacement of the sensor
- Grounding issues in the circuit
Common misdiagnosis for B1252 Air Temperature Internal Sensor Circuit Short To Battery
- Faulty air temperature sensor
- Wiring issues or shorts in the harness
- Faulty engine control module (ECM)
- Incorrectly installed or damaged connectors
- Issues with the climate control module
- Faulty ambient temperature sensor
- Problems with the vehicle’s battery or charging system
Common Troubleshooting Steps
When dealing with OBD-II code B1252, which indicates an “Air Temperature Internal Sensor Circuit Short To Battery,” there are several common troubleshooting steps you can follow to diagnose and potentially resolve the issue. Here’s a structured approach:
- Check the Vehicle’s Manual: Refer to the vehicle’s service manual for specific information regarding the air temperature sensor and its circuit.
- Visual Inspection: **Wiring and Connectors: Inspect the wiring harness and connectors associated with the air temperature sensor for any signs of damage, corrosion, or loose connections.
- **Sensor Condition: Check the air temperature sensor itself for physical damage or contamination.
- Test the Sensor: **Resistance Check: Use a multimeter to measure the resistance of the air temperature sensor. Compare the readings to the specifications in the service manual.
- **Voltage Check: With the ignition on (engine off), check the voltage at the sensor connector. It should match the expected voltage as per the specifications.
- Check for Short Circuits: **Continuity Test: Perform a continuity test on the wiring to check for shorts to battery voltage. Disconnect the sensor and check for continuity between the sensor wire and the battery positive terminal.
- **Ground Check: Ensure that the ground connection for the sensor is intact and not shorted to battery voltage.
- Scan for Additional Codes: Use an OBD-II scanner to check for any other related trouble codes that may provide additional context or indicate other issues in the system.
- Inspect Related Components: Check other components that may be related to the air temperature sensor circuit, such as the Engine Control Module (ECM) or any associated relays and fuses.
- Clear the Code: After performing the checks and repairs, clear the trouble code using an OBD-II scanner and take the vehicle for a test drive to see if the code reappears.
- Professional Diagnosis: If the issue persists after performing the above steps, consider seeking help from a professional mechanic or technician who can perform more advanced diagnostics.
- Replace the Sensor (if necessary): If the sensor is found to be faulty during testing, replace it with a new one and recheck the system.
- Monitor the System: After repairs, monitor the vehicle’s performance and check for any recurring codes to ensure the issue has been resolved. By following these steps, you should be able to identify and address the cause of the B1252 code effectively.