C1251 – OBD-II DTC

OBD-II DTC C1251 – ABS Inlet Valve Coil LR Circuit Open

DTC C1251 meaning

DTC C1251 refers to a diagnostic trouble code indicating an issue with the ABS (Anti-lock Braking System) inlet valve coil for the left rear (LR) circuit. This code is triggered when the vehicle’s onboard diagnostic system detects an open circuit in the inlet valve coil, which is responsible for controlling brake fluid flow to the left rear wheel during ABS operation.

DTC C1251 symptoms

Common symptoms associated with DTC C1251 may include:

• Illumination of the ABS warning light on the dashboard
• Decreased braking performance, especially during hard braking
• Inconsistent or erratic ABS operation
• Potential activation of the traction control system warning light

DTC C1251 causes

Several factors can lead to the triggering of DTC C1251, including:

• Faulty inlet valve coil for the left rear wheel
• Wiring issues such as frayed or damaged wires in the circuit
• Corrosion or poor connections at the valve coil connector
• Malfunctioning ABS control module

DTC C1251 seriousness

DTC C1251 is considered a serious issue as it directly affects the vehicle’s braking system. If left unaddressed, it can lead to:

• Increased stopping distances
• Loss of ABS functionality
• Potential safety hazards during emergency braking situations

How to diagnose DTC C1251

To diagnose DTC C1251, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC C1251.
2. Inspect the wiring and connectors associated with the left rear inlet valve coil for any visible damage or corrosion.
3. Perform a continuity test on the inlet valve coil circuit to check for an open circuit.
4. Test the inlet valve coil itself for proper resistance and functionality.
5. Check the ABS control module for any additional fault codes or issues.

How to fix DTC C1251 step-by-step instructions

To fix DTC C1251, follow these steps:

1. Repair or replace any damaged wiring or connectors found during the diagnosis.
2. If the inlet valve coil is faulty, replace it with a new component.
3. Ensure all connections are secure and free of corrosion.
4. Clear the DTC using an OBD-II scanner.
5. Test drive the vehicle to ensure the ABS system is functioning correctly and the DTC does not reappear.

How to erase DTC C1251

To erase DTC C1251, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Access the trouble codes menu on the scanner.
3. 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 verify that the ABS warning light is off.

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