What is an OBD2 code?

An OBD2 (On-Board Diagnostics) code is a diagnostic trouble code (DTC) generated by your vehicle's computer system when it detects a problem. These codes help identify specific issues with your vehicle's engine, transmission, emissions, or other systems.

How do I read OBD2 codes?

To read OBD2 codes, you'll need an OBD2 scanner. Plug it into your vehicle's OBD2 port (usually located under the dashboard), turn your key to the 'ON' position, and follow your scanner's instructions to retrieve the codes. Each code starts with a letter (P, B, C, or U) followed by four numbers.

What do the different types of OBD2 codes mean?

OBD2 codes are categorized by their first letter: P (Powertrain) for engine and transmission issues, B (Body) for interior systems like airbags, C (Chassis) for mechanical systems like brakes, and U (Network) for computer and module communication problems.

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Home » OBD2 Codes » C0555

Code C0555

Symptoms

• ABS warning light on

• Traction control system malfunction

• Inaccurate speed readings

Common Causes

• Incorrect wheel speed sensor installed

• Sensor not compatible with vehicle's system

• Aftermarket sensor with wrong specifications

Glossary

OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics in vehicles.

ABS: Anti-lock Braking System, a safety system that prevents the wheels from locking up during braking.

Related Codes

• C0550

• C0561

Laymans terms

The car's computer thinks the wrong part is installed on one of the wheels, which might confuse the car about how fast it's going.

Explanation

The vehicle's control module has detected that the left front wheel speed sensor is not the correct part for the vehicle.

Technical description

The C0555 code indicates that the control module has identified an incorrect component installed for the left front wheel speed sensor. This could be due to a mismatch in the sensor's specifications or a completely different sensor being installed.

Diagnosis steps

• Verify the part number of the installed sensor

• Check compatibility with the vehicle's specifications

• Inspect wiring and connections for any issues

Repair procedures

• Replace the incorrect sensor with the correct part

• Ensure the new sensor is properly connected

• Clear the code and test drive to verify the fix

Tools required

• OBD-II scanner

• Multimeter

• Socket set

Estimated repair cost

$100 - $300

Difficulty level

Moderate

Commonly affected vehicles

• Chevrolet Silverado

• GMC Sierra

• Cadillac Escalade

Preventive measures

• Use OEM parts for replacements

• Verify part compatibility before installation

• Regularly inspect wheel speed sensors

Error code type

Sensor Issue

User experience recommendations

• Consult a professional mechanic if unsure

• Avoid using non-compatible aftermarket parts

Warranty information

Check with the vehicle's manufacturer for warranty coverage on sensor replacements.

Historical data

This code has been associated with incorrect part installations, particularly when aftermarket parts are used.

Urgency level

Moderate – It may affect vehicle safety systems like ABS and traction control.

Legal and safety notice

Driving with a faulty wheel speed sensor can affect vehicle safety systems, potentially leading to unsafe driving conditions.

Testing conditions

• Vehicle stationary

• Engine running

Component location

The left front wheel speed sensor is located near the wheel hub of the left front wheel.

FAQs

Q: Can I drive with a C0555 code?
A: It's not recommended, as it can affect safety systems like ABS and traction control.

Q: How do I know if the sensor is incorrect?
A: Check the part number and ensure it matches the vehicle's specifications.

Last updated: Jun 8, 2026 • Source: internal database

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