C1191 – OBD-II DTC

OBD-II DTC C1191 – Speed Wheel Sensor LF Input Short Circuit To Ground

DTC C1191 meaning

DTC C1191 refers to a diagnostic trouble code indicating a short circuit to ground in the left front speed wheel sensor input. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components to ensure proper operation. The left front speed wheel sensor is crucial for the vehicle’s anti-lock braking system (ABS) and traction control system, as it provides real-time data on wheel speed.

DTC C1191 symptoms

Common symptoms associated with DTC C1191 may include:

• Illumination of the ABS warning light on the dashboard
• Loss of ABS functionality
• Inconsistent or erratic braking performance
• Traction control system malfunctions
• Potential activation of the brake warning light

DTC C1191 causes

Several factors can lead to the occurrence of DTC C1191, including:

• Damaged or frayed wiring in the left front speed wheel sensor circuit
• Corroded or loose electrical connectors
• Faulty left front speed wheel sensor
• Short circuit in the sensor circuit due to moisture or debris
• Issues with the ABS control module

DTC C1191 seriousness

DTC C1191 is considered a serious issue as it affects the vehicle’s braking system. The ABS and traction control systems rely on accurate wheel speed data to function correctly. If these systems are compromised, it can lead to decreased vehicle stability and increased stopping distances, especially in slippery conditions. Therefore, it is essential to address this code promptly to ensure safe vehicle operation.

How to diagnose DTC C1191

To diagnose DTC C1191, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the C1191 code.
2. Inspect the left front speed wheel sensor wiring and connectors for damage or corrosion.
3. Check the resistance of the left front speed wheel sensor using a multimeter.
4. Test the voltage supply to the sensor while the vehicle is running.
5. Examine the ABS control module for any faults or issues.

How to fix DTC C1191 step-by-step instructions

To fix DTC C1191, follow these steps:

1. Disconnect the vehicle’s battery to ensure safety while working on electrical components.
2. Inspect and repair any damaged wiring or connectors related to the left front speed wheel sensor.
3. If the sensor is faulty, replace it with a new one.
4. Reconnect the battery and clear the DTC using an OBD-II scanner.
5. Test drive the vehicle to ensure the ABS and traction control systems are functioning correctly and that the code does not reappear.

How to erase DTC C1191

To erase DTC C1191, 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 trouble codes.
5. Disconnect the scanner and start the vehicle to verify that the code has been erased and does not return.

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