B1250 – OBD-II DTC

OBD-II DTC B1250 – Air Temperature Internal Sensor Circuit Failure

DTC B1250 meaning

DTC B1250 refers to a diagnostic trouble code indicating a failure in the air temperature internal sensor circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various components and systems within a vehicle. The air temperature sensor is crucial for the engine control module (ECM) to adjust fuel mixture and optimize engine performance based on the ambient air temperature.

DTC B1250 symptoms

When the DTC B1250 is triggered, several symptoms may be observed, including:

• Check Engine Light (CEL) illuminated
• Increased fuel consumption
• Engine performance issues, such as rough idling or stalling
• Difficulty starting the engine
• Unusual engine temperature readings

DTC B1250 causes

There are several potential causes for the DTC B1250 code, including:

• Faulty air temperature sensor
• Wiring issues, such as shorts or open circuits
• Corroded or loose electrical connectors
• Faulty engine control module (ECM)
• Software issues within the ECM

DTC B1250 seriousness

The seriousness of DTC B1250 can vary depending on the underlying issue. While it may not cause immediate safety concerns, it can lead to:

• Decreased fuel efficiency
• Increased emissions
• Potential engine damage if left unaddressed

It is advisable to diagnose and repair the issue promptly to maintain optimal vehicle performance.

How to diagnose DTC B1250

To diagnose DTC B1250, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1250 code.
2. Inspect the air temperature sensor and its wiring for visible damage.
3. Check the electrical connectors for corrosion or loose connections.
4. Test the air temperature sensor with a multimeter to ensure it is functioning correctly.
5. Examine the ECM for any software updates or faults.

How to fix DTC B1250 step-by-step instructions

To fix DTC B1250, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety.
2. Inspect and repair any damaged wiring or connectors related to the air temperature sensor.
3. If the air temperature sensor is faulty, replace it with a new one.
4. Reconnect the battery and clear the DTC using an OBD-II scanner.
5. Start the engine and monitor for any reoccurrence of the DTC.

How to erase DTC B1250

To erase DTC B1250, 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 option to clear or erase trouble codes on the scanner.
4. Confirm the action to erase the DTC.
5. Disconnect the scanner and start the engine to ensure the code does not return.

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