C1261 – OBD-II DTC

OBD-II DTC C1261 – Speed Wheel LR Comparison Failure

DTC C1261 meaning

DTC C1261 refers to a “Speed Wheel LR Comparison Failure.” This diagnostic trouble code indicates that the vehicle’s onboard diagnostic system has detected a discrepancy in the speed readings from the left rear wheel speed sensor compared to the other wheel speed sensors. This can affect the vehicle’s stability control and anti-lock braking system (ABS) performance.

DTC C1261 symptoms

Common symptoms associated with DTC C1261 may include:

• Illumination of the ABS warning light on the dashboard
• Decreased effectiveness of the ABS system
• Unusual braking behavior, such as locking up or skidding
• Inconsistent traction control operation
• Possible activation of the stability control system

DTC C1261 causes

Several factors can lead to the triggering of DTC C1261, including:

• Faulty left rear wheel speed sensor
• Damaged wiring or connectors related to the wheel speed sensor
• Issues with the ABS control module
• Incorrectly installed or malfunctioning brake components
• Wheel bearing problems affecting sensor readings

DTC C1261 seriousness

DTC C1261 is considered a serious issue as it can compromise the vehicle’s braking and stability control systems. If left unaddressed, it may lead to reduced vehicle control, especially in adverse driving conditions, increasing the risk of accidents.

How to diagnose DTC C1261

To diagnose DTC C1261, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC C1261.
2. Inspect the left rear wheel speed sensor and its wiring for any visible damage or disconnections.
3. Check the resistance and voltage output of the left rear wheel speed sensor.
4. Compare the readings from the left rear sensor with those from the other wheel speed sensors.
5. Examine the ABS control module for any fault codes or issues.
6. Perform a road test to observe the behavior of the ABS and traction control systems.

How to fix DTC C1261 step-by-step instructions

To fix DTC C1261, follow these steps:

1. Inspect and repair any damaged wiring or connectors related to the left rear wheel speed sensor.
2. If the wheel speed sensor is faulty, replace it with a new one.
3. Ensure that the sensor is properly installed and aligned.
4. Check the ABS control module for any updates or necessary repairs.
5. Clear the DTC using an OBD-II scanner.
6. Perform a road test to verify that the issue has been resolved and that the ABS and traction control systems are functioning correctly.

How to erase DTC C1261

To erase DTC C1261, 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 reappear.

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