C1237 – OBD-II DTC

OBD-II DTC C1237 – Speed Wheel Rear Input Signal Missing

DTC C1237 meaning

DTC C1237 refers to a diagnostic trouble code indicating that the speed wheel rear input signal is missing. This code is typically associated with the vehicle’s anti-lock braking system (ABS) or traction control system. The absence of this signal can affect the vehicle’s ability to monitor wheel speed, which is crucial for proper operation of these systems.

DTC C1237 symptoms

Common symptoms associated with DTC C1237 may include:

• Illumination of the ABS warning light on the dashboard
• Loss of traction control functionality
• Inconsistent braking performance
• Potential activation of the ABS during normal braking

DTC C1237 causes

Several factors can lead to the occurrence of DTC C1237, including:

• Faulty wheel speed sensor at the rear
• Damaged wiring or connectors related to the wheel speed sensor
• Corrosion or dirt on the sensor or its mounting
• Issues with the ABS control module
• Faulty brake system components affecting sensor operation

DTC C1237 seriousness

DTC C1237 is considered a serious issue as it can compromise the vehicle’s braking and stability control systems. If left unaddressed, it may lead to decreased vehicle safety, especially in slippery or emergency conditions. It is advisable to diagnose and repair this code promptly to ensure optimal vehicle performance.

How to diagnose DTC C1237

To diagnose DTC C1237, follow these steps:

• Use an OBD-II scanner to confirm the presence of the code.
• Inspect the rear wheel speed sensor for physical damage or disconnection.
• Check the wiring and connectors for signs of wear, corrosion, or damage.
• Test the wheel speed sensor’s output using a multimeter.
• Examine the ABS control module for any faults or issues.

How to fix DTC C1237 step-by-step instructions

To fix DTC C1237, follow these step-by-step instructions:

1. Start by verifying the DTC with an OBD-II scanner.
2. Inspect the rear wheel speed sensor for any visible damage or disconnection.
3. If the sensor is damaged, replace it with a new one.
4. Check the wiring and connectors for any signs of damage or corrosion.
5. Repair or replace any damaged wiring or connectors as necessary.
6. Test the wheel speed sensor output to ensure it is functioning correctly.
7. Clear the DTC using the OBD-II scanner and take the vehicle for a test drive.
8. Monitor for any reoccurrence of the code or related symptoms.

How to erase DTC C1237

To erase DTC C1237, follow these steps:

• Connect an OBD-II scanner to the vehicle’s diagnostic port.
• Turn on the vehicle’s ignition without starting the engine.
• Access the scanner’s menu and select the option to clear or erase trouble codes.
• Confirm the action and wait for the scanner to complete the process.
• Disconnect the scanner and start the vehicle to ensure the code does not reappear.

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