B1491 – OBD-II DTC

OBD-II DTC B1491 – Ignition Cylinder Sensor Circuit Failure

DTC B1491 meaning

DTC B1491 refers to a failure in the ignition cylinder sensor circuit. This diagnostic trouble code indicates that the vehicle’s onboard diagnostic system has detected an issue with the sensor responsible for monitoring the position of the ignition cylinder. The ignition cylinder sensor plays a crucial role in ensuring that the vehicle’s ignition system operates correctly, allowing the engine to start and run smoothly.

DTC B1491 symptoms

Common symptoms associated with DTC B1491 may include:

• Engine not starting or cranking
• Intermittent starting issues
• Dashboard warning lights illuminated
• Difficulty turning the ignition key
• Loss of power to electrical components

DTC B1491 causes

Several factors can lead to the occurrence of DTC B1491, including:

• Faulty ignition cylinder sensor
• Wiring issues, such as frayed or damaged wires
• Corroded or loose electrical connectors
• Faulty ignition switch
• Issues with the vehicle’s power supply

DTC B1491 seriousness

DTC B1491 is considered a serious issue as it can prevent the vehicle from starting. If the ignition cylinder sensor is malfunctioning, it may lead to further complications in the ignition system, potentially causing additional damage or safety concerns. It is advisable to address this code promptly to ensure reliable vehicle operation.

How to diagnose DTC B1491

To diagnose DTC B1491, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC B1491.
2. Inspect the ignition cylinder sensor and its wiring for visible damage.
3. Check the electrical connectors for corrosion or looseness.
4. Test the ignition cylinder sensor using a multimeter to ensure it is functioning within specifications.
5. Examine the ignition switch for proper operation.
6. Clear the DTC and perform a test drive to see if the code reappears.

How to fix DTC B1491 step-by-step instructions

To fix DTC B1491, follow these steps:

1. Disconnect the vehicle’s battery to ensure safety.
2. Inspect and repair any damaged wiring or connectors related to the ignition cylinder sensor.
3. If the ignition cylinder sensor is faulty, replace it with a new one.
4. Check and, if necessary, replace the ignition switch.
5. Reconnect the battery and clear the DTC using an OBD-II scanner.
6. Perform a test drive to verify that the issue has been resolved and the code does not return.

How to erase DTC B1491

To erase DTC B1491, 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 ensure the code does not reappear.

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