B1255 – OBD-II DTC

OBD-II DTC B1255 – Air Temperature External Sensor Circuit Open

DTC B1255 meaning

DTC B1255 refers to a diagnostic trouble code indicating an issue with the Air Temperature External Sensor Circuit. Specifically, it signifies that the circuit is open, meaning there is a break in the electrical connection that prevents the sensor from sending accurate temperature readings to the vehicle’s control module.

DTC B1255 symptoms

Common symptoms associated with DTC B1255 may include:

• Inaccurate air temperature readings
• Malfunctioning climate control system
• Increased fuel consumption
• Check Engine Light illuminated
• Potential issues with engine performance

DTC B1255 causes

Several factors can lead to the occurrence of DTC B1255, including:

• Faulty air temperature sensor
• Damaged wiring or connectors in the sensor circuit
• Corrosion or poor connections at the sensor or control module
• Short circuits or open circuits in the wiring harness
• Issues with the vehicle’s control module

DTC B1255 seriousness

DTC B1255 is considered a moderate issue. While it may not cause immediate catastrophic failure, it can lead to poor engine performance and increased emissions. Ignoring this code can result in further complications, such as damage to other components or systems in the vehicle.

How to diagnose DTC B1255

To diagnose DTC B1255, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the DTC.
2. Inspect the air temperature sensor and its wiring for visible damage.
3. Check the electrical connections for corrosion or looseness.
4. Test the air temperature sensor with a multimeter to ensure it is functioning correctly.
5. Examine the vehicle’s control module for any related fault codes.
6. Perform a continuity test on the wiring harness to check for breaks.

How to fix DTC B1255 step-by-step instructions

To fix DTC B1255, follow these steps:

1. Identify and replace the faulty air temperature sensor if necessary.
2. Repair or replace any damaged wiring or connectors in the sensor circuit.
3. Clean any corrosion from electrical connections.
4. Ensure all connections are secure and properly seated.
5. Clear the DTC using an OBD-II scanner.
6. Test drive the vehicle to ensure the code does not return.

How to erase DTC B1255

To erase DTC B1255, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
4. Confirm the action to clear the trouble codes.
5. Disconnect the scanner and start the vehicle to check for any reoccurrence of the code.

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