C1143 – OBD-II DTC

OBD-II DTC C1143 – Wheel Speed Sensor LR Tone Ring Tooth Missing Fault

DTC C1143 meaning

DTC C1143 refers to a fault in the vehicle’s wheel speed sensor system, specifically indicating that there is a missing tooth on the tone ring of the left rear wheel speed sensor. The tone ring is a critical component that works in conjunction with the wheel speed sensor to monitor the rotational speed of the wheel. A missing tooth can lead to inaccurate readings, affecting the vehicle’s stability control and anti-lock braking systems.

DTC C1143 symptoms

Common symptoms associated with DTC C1143 may include:

• Illumination of the ABS warning light on the dashboard
• Decreased effectiveness of the anti-lock braking system
• Unusual behavior of the traction control system
• Inconsistent or erratic speedometer readings
• Potential loss of stability control features

DTC C1143 causes

Several factors can lead to the occurrence of DTC C1143, including:

• Physical damage to the tone ring, such as cracks or missing teeth
• Corrosion or dirt buildup on the wheel speed sensor or tone ring
• Faulty wheel speed sensor itself
• Wiring issues, such as frayed or broken wires connected to the sensor
• Improper installation of the tone ring or sensor

DTC C1143 seriousness

The seriousness of DTC C1143 can vary based on the vehicle’s use and condition. However, it is generally considered a moderate to high priority issue because:

• It can compromise the effectiveness of the ABS and traction control systems.
• It may lead to decreased vehicle safety, especially in slippery conditions.
• Ignoring the fault can result in further damage to the braking system or related components.

How to diagnose DTC C1143

To diagnose DTC C1143, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC C1143.
2. Inspect the left rear wheel speed sensor and tone ring for visible damage or missing teeth.
3. Check the wiring and connectors for any signs of wear, corrosion, or disconnection.
4. Test the wheel speed sensor’s resistance and output signal using a multimeter.
5. Clear the DTC and perform a road test to see if the code reappears.

How to fix DTC C1143 step-by-step instructions

To fix DTC C1143, follow these step-by-step instructions:

1. Inspect the left rear tone ring for any missing teeth or damage.
2. If the tone ring is damaged, replace it with a new one.
3. Clean the wheel speed sensor and tone ring area to remove any dirt or debris.
4. Check the wheel speed sensor for proper operation replace it if faulty.
5. Examine the wiring and connectors for any issues
   

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