C1124 – OBD-II DTC

OBD-II DTC C1124 – Input shaft speed signal missing/faulted

DTC C1124 meaning

DTC C1124 refers to a diagnostic trouble code indicating that the input shaft speed signal is missing or has faulted. This code is typically associated with the vehicle’s transmission system, where the input shaft speed sensor is responsible for monitoring the rotational speed of the input shaft. A malfunction in this sensor can lead to improper transmission operation and affect vehicle performance.

DTC C1124 symptoms

Common symptoms associated with DTC C1124 may include:

• Transmission slipping or erratic shifting
• Check Engine Light or warning light illuminated
• Reduced engine power or performance
• Unusual noises from the transmission
• Difficulty in engaging gears

DTC C1124 causes

Several factors can lead to the occurrence of DTC C1124, including:

• Faulty input shaft speed sensor
• Wiring issues, such as damaged or corroded connectors
• Faulty transmission control module (TCM)
• Low transmission fluid levels or contamination
• Mechanical issues within the transmission

DTC C1124 seriousness

DTC C1124 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 C1124

To diagnose DTC C1124, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the code.
2. Inspect the input shaft speed sensor and its wiring for any visible damage or corrosion.
3. Check the transmission fluid level and condition.
4. Test the input shaft speed sensor using a multimeter to ensure it is functioning correctly.
5. Examine the transmission control module for any faults or updates.
6. Clear the code and perform a road test to see if the code reappears.

How to fix DTC C1124 step-by-step instructions

To fix DTC C1124, follow these steps:

1. Inspect and repair any damaged wiring or connectors related to the input shaft speed sensor.
2. If the input shaft speed sensor is faulty, replace it with a new one.
3. Ensure the transmission fluid is at the correct level and replace it if contaminated.
4. Reprogram or replace the transmission control module if necessary.
5. Clear the DTC using an OBD-II scanner.
6. Perform a road test to verify that the issue has been resolved and the code does not return.

How to erase DTC C1124

To erase DTC C1124, 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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