C1429 – OBD-II DTC

OBD-II DTC C1429 – Input-shaft-speed input circuit failure

DTC C1429 meaning

DTC C1429 refers to an Input-shaft-speed input circuit failure. This diagnostic trouble code indicates that the vehicle’s onboard diagnostic system has detected an issue with the input shaft speed sensor or its associated circuit. The input shaft speed sensor is crucial for monitoring the rotational speed of the input shaft in the transmission, which is essential for proper transmission operation and performance.

DTC C1429 symptoms

Common symptoms associated with DTC C1429 may include:

• Transmission slipping or erratic shifting
• Check Engine Light or warning light illuminated
• Reduced engine performance
• Unusual noises from the transmission
• Inability to engage certain gears

DTC C1429 causes

Several factors can lead to the occurrence of DTC C1429, including:

• Faulty input shaft speed sensor
• Wiring issues such as shorts, opens, or corrosion in the sensor circuit
• Connector problems, including loose or damaged connectors
• Faulty transmission control module (TCM)
• Mechanical issues within the transmission

DTC C1429 seriousness

DTC C1429 is considered a serious issue as it can affect the vehicle’s transmission performance. If left unaddressed, it may lead to further transmission damage, reduced drivability, and potential safety hazards. It is advisable to diagnose and repair the issue promptly to ensure safe and reliable vehicle operation.

How to diagnose DTC C1429

To diagnose DTC C1429, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC C1429.
2. Inspect the input shaft speed sensor and its wiring for visible damage or corrosion.
3. Check the sensor connector for proper connection and any signs of wear.
4. Test the input shaft speed sensor using a multimeter to ensure it is functioning within specifications.
5. Examine the transmission control module for any faults or issues.
6. Perform a road test to observe transmission behavior and verify if the code returns.

How to fix DTC C1429 step-by-step instructions

To fix DTC C1429, follow these steps:

1. Repair or replace any damaged wiring or connectors associated with the input shaft speed sensor.
2. If the input shaft speed sensor is faulty, replace it with a new one.
3. Clear any stored DTCs using an OBD-II scanner.
4. Perform a road test to ensure the issue is resolved and the code does not return.
5. If the problem persists, further diagnose the transmission control module and other related components.

How to erase DTC C1429

To erase DTC C1429, 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 check if the code reappears.

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