C1222 – OBD-II DTC

OBD-II DTC C1222 – Speed Wheel Mismatch

DTC C1222 meaning

DTC C1222 refers to a “Speed Wheel Mismatch” error detected by the On-Board Diagnostics II (OBD-II) system. This code indicates that there is a discrepancy between the speed readings from the wheel speed sensors. The vehicle’s anti-lock braking system (ABS) relies on accurate wheel speed data to function properly, and a mismatch can lead to issues with braking performance and stability control.

DTC C1222 symptoms

Common symptoms associated with DTC C1222 may include:

• Illumination of the ABS warning light on the dashboard
• Inconsistent or erratic ABS operation
• Loss of traction control functionality
• Unusual braking behavior, such as locking up or skidding

DTC C1222 causes

Several factors can lead to the triggering of DTC C1222, including:

• Faulty wheel speed sensors
• Damaged wiring or connectors related to the wheel speed sensors
• Incorrectly installed or malfunctioning ABS control module
• Differences in tire sizes or types on the vehicle
• Issues with the vehicle’s electronic control unit (ECU)

DTC C1222 seriousness

DTC C1222 is considered a serious issue as it affects the vehicle’s braking system and overall safety. If left unaddressed, it can lead to compromised braking performance, increasing the risk of accidents. It is essential to diagnose and repair the underlying issues promptly to ensure safe vehicle operation.

How to diagnose DTC C1222

To diagnose DTC C1222, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the C1222 code.
2. Inspect the wheel speed sensors for physical damage or disconnection.
3. Check the wiring and connectors for signs of wear, corrosion, or loose connections.
4. Verify that all tires are of the same size and type.
5. Test the wheel speed sensors using a multimeter to ensure they are functioning correctly.
6. Examine the ABS control module for any faults or error codes.

How to fix DTC C1222 step-by-step instructions

To fix DTC C1222, follow these steps:

1. Address any issues found during the diagnosis, such as replacing faulty wheel speed sensors.
2. Repair or replace damaged wiring or connectors as needed.
3. Ensure all tires are matched in size and type to prevent discrepancies.
4. Reinstall or replace the ABS control module if it is found to be faulty.
5. Clear the DTC using an OBD-II scanner and perform a test drive to verify that the issue is resolved.

How to erase DTC C1222

To erase DTC C1222, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the vehicle’s ignition without starting the engine.
3. Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
4. Confirm the action to clear the codes from the vehicle’s memory.
5. Disconnect the scanner and start the vehicle to ensure the code does not reappear.

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