C0221

The C0221 diagnostic trouble code means the chassis control module has identified a park brake applied with vehicle in motion problem. This code relates to a chassis sensor providing incorrect or missing data to the control module. Chassis sensor issues can affect braking, steering, and stability control performance. This guide covers everything you need to know about this topic, including common causes, step-by-step solutions, and answers to frequently asked questions.

Here are the key things to understand: Incorrect sensor data shown on scan tool. Cruise control not functioning. Idle speed fluctuations. Poor engine performance. Understanding these fundamentals will help you diagnose and resolve this issue more effectively.

The most common reasons this occurs include: Faulty PCM/ECM not reading sensor correctly. Incorrect sensor installed. Open or shorted sensor wiring. Sensor out of calibration. Identifying the root cause is the first step toward finding the right solution.

To resolve this, follow these recommended steps: Connect an OBD-II scanner and read all stored trouble codes and freeze frame data. Locate the specific sensor referenced by the code. Inspect the sensor connector for corrosion, damage, or loose pins. Test the sensor output using a multimeter or scan tool live data. Check the wiring between the sensor and the PCM for opens or shorts. If these steps do not resolve the issue, consider consulting additional resources or a qualified professional.

This article is part of our Chassis (C) collection on OBD Codes. We provide comprehensive, up-to-date information to help you find solutions quickly.