C1165 – OBD-II DTC

OBD-II DTC C1165 – Speed Wheel Sensor RR Input Circuit Failure

DTC C1165 meaning

DTC C1165 refers to a diagnostic trouble code indicating a failure in the rear right speed wheel sensor input circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components to ensure proper functionality. The rear right speed wheel sensor is responsible for providing the vehicle’s speed data to the anti-lock braking system (ABS) and traction control system (TCS). When the system detects an issue with this sensor or its circuit, it triggers the C1165 code.

DTC C1165 symptoms

Common symptoms associated with DTC C1165 may include:

• Illumination of the ABS warning light on the dashboard
• Inconsistent or erratic speedometer readings
• Loss of traction control functionality
• Increased stopping distances due to ABS malfunction
• Unusual noises from the braking system

DTC C1165 causes

Several factors can lead to the triggering of DTC C1165, including:

• Faulty rear right speed wheel sensor
• Damaged or corroded wiring in the sensor circuit
• Poor electrical connections or loose connectors
• Faulty ABS control module
• Mechanical issues such as a damaged wheel bearing

DTC C1165 seriousness

DTC C1165 is considered a serious issue as it affects the vehicle’s braking system and overall safety. The malfunction of the ABS can lead to reduced braking efficiency, especially in slippery conditions. It is crucial to address this code promptly to ensure safe vehicle operation.

How to diagnose DTC C1165

To diagnose DTC C1165, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the C1165 code.
2. Inspect the rear right speed wheel sensor for visible damage or wear.
3. Check the wiring and connectors for signs of corrosion or loose connections.
4. Test the sensor’s resistance and voltage output according to manufacturer specifications.
5. Examine the ABS control module for faults or error codes.
6. Perform a road test to observe the behavior of the ABS and traction control systems.

How to fix DTC C1165 step-by-step instructions

To fix DTC C1165, follow these steps:

1. Clear the DTC using an OBD-II scanner.
2. If the code returns, replace the rear right speed wheel sensor.
3. Repair or replace any damaged wiring or connectors in the sensor circuit.
4. Ensure all electrical connections are secure and free of corrosion.
5. Test the ABS control module for proper operation and replace if necessary.
6. Recheck the system for any remaining codes and perform a road test to confirm the fix.

How to erase DTC C1165

To erase DTC C1165, 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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