C1721 – OBD-II DTC

OBD-II DTC C1721 – Air Suspension Height Sensor Power Circuit Open

DTC C1721 meaning

DTC C1721 refers to an issue with the air suspension height sensor power circuit being open. This means that the power supply to the height sensor, which is responsible for measuring the vehicle’s height and adjusting the air suspension accordingly, is interrupted or not functioning properly. An open circuit can prevent the sensor from receiving the necessary voltage to operate, leading to potential issues with the air suspension system.

DTC C1721 symptoms

Common symptoms associated with DTC C1721 may include:

• Warning lights on the dashboard, particularly the air suspension warning light.
• Inconsistent or incorrect vehicle height adjustments.
• Rough ride quality due to improper suspension settings.
• Inability to raise or lower the vehicle as intended.

DTC C1721 causes

Several factors can lead to the occurrence of DTC C1721, including:

• Damaged or frayed wiring in the height sensor power circuit.
• Corroded or loose electrical connections.
• Faulty height sensor itself.
• Issues with the air suspension control module.
• Blown fuses related to the air suspension system.

DTC C1721 seriousness

DTC C1721 is considered a serious issue as it directly affects the vehicle’s air suspension system. If left unaddressed, it can lead to:

• Increased wear and tear on suspension components.
• Compromised vehicle handling and safety.
• Potential damage to the air suspension system.

How to diagnose DTC C1721

To diagnose DTC C1721, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC C1721.
2. Inspect the wiring and connectors related to the height sensor for any visible damage or corrosion.
3. Check the vehicle’s fuse box for any blown fuses associated with the air suspension system.
4. Test the voltage at the height sensor connector to ensure it is receiving power.
5. Perform a continuity test on the wiring to check for any breaks in the circuit.
6. If necessary, replace the height sensor or repair any damaged wiring.

How to fix DTC C1721 step-by-step instructions

To fix DTC C1721, follow these step-by-step instructions:

1. Gather necessary tools, including an OBD-II scanner, multimeter, and basic hand tools.
2. Clear the DTC using the OBD-II scanner and take the vehicle for a test drive to see if the code returns.
3. If the code reappears, visually inspect the height sensor wiring and connectors for damage.
4. Repair or replace any damaged wiring or connectors found during the inspection.
5. Check the fuses related to the air suspension system and replace any that are blown.
6. Test the height sensor with a multimeter to ensure it is functioning correctly.
7. If the sensor is faulty, replace it with a new one.
8. Reconnect all components and clear the DTC again.
9. Perform a final test drive to confirm that the issue is resolved.

How to erase DTC C1721

To erase DTC C1721, follow these steps:

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

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