C1751 – OBD-II DTC

OBD-II DTC C1751 – Vehicle Speed Sensor # 1 Output Circuit Short to Vbatt

DTC C1751 meaning

DTC C1751 refers to a diagnostic trouble code indicating a problem with the Vehicle Speed Sensor # 1 output circuit. Specifically, it signifies that there is a short circuit in the output circuit of the vehicle speed sensor to the battery voltage (Vbatt). This can lead to incorrect speed readings and affect various systems that rely on accurate vehicle speed data.

DTC C1751 symptoms

Common symptoms associated with DTC C1751 may include:

• Inaccurate speedometer readings
• Erratic or fluctuating speed readings
• Malfunction indicator lamp (MIL) illuminated
• Transmission shifting issues
• Potential impact on cruise control functionality

DTC C1751 causes

Several factors can lead to the occurrence of DTC C1751, including:

• Faulty vehicle speed sensor
• Wiring issues, such as shorts or open circuits
• Corroded or damaged connectors
• Faulty engine control module (ECM)
• Electrical interference from other components

DTC C1751 seriousness

The seriousness of DTC C1751 can vary based on the vehicle’s operation. While it may not cause immediate safety concerns, it can lead to:

• Inaccurate speed readings affecting driving performance
• Transmission problems that could lead to further damage
• Increased wear on vehicle components due to improper shifting

It is advisable to address this code promptly to avoid potential complications.

How to diagnose DTC C1751

To diagnose DTC C1751, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC C1751.
2. Inspect the vehicle speed sensor and its wiring for visible damage or corrosion.
3. Check the sensor’s output voltage using a multimeter while the vehicle is in motion.
4. Examine the connectors for proper seating and signs of wear.
5. Test the continuity of the wiring between the sensor and the ECM.
6. Check for any additional DTCs that may provide further insight into the issue.

How to fix DTC C1751 step-by-step instructions

To fix DTC C1751, follow these steps:

1. Clear the DTC using an OBD-II scanner.
2. Inspect and repair any damaged wiring or connectors related to the vehicle speed sensor.
3. Replace the vehicle speed sensor if it is found to be faulty.
4. Ensure all connections are secure and free from corrosion.
5. Recheck the system by taking the vehicle for a test drive to verify proper operation.
6. Use the OBD-II scanner to confirm that the DTC does not reappear.

How to erase DTC C1751

To erase DTC C1751, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn the ignition key to the “On” position without starting the engine.
3. Access the scanner’s menu and select the option to clear or erase trouble codes.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and start the vehicle to ensure the code does not return.

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