Step-by-Step Instructions:

Identify the Symptoms:

Stick the key in the ignition with the door open.

Note any unusual messages on the screen, such as "Take key from ignition". Try turning the key to the right and observe dashboard lights. If none illuminate, it could be a sign of a steering lock issue. Check if you can operate the windows and the sunroof. A malfunctioning steering lock might affect these functions.

Using a Diagnostic Scanner:

Connect the diagnostic scanner to the OBD port under the dashboard.

Navigate to the EIS (Electronic Ignition Switch) module using the scanner.

Select Vehicle and Module:

Manually select your C300 model, specifying the gasoline left-hand steering variant.

Locate and select the EIS module (sometimes referred to as EZS - Electronic Ignition Switch).

Read Fault Codes:

Read the fault codes stored in the EIS module.

Look for codes related to power supply issues and electronic steering lock malfunctions.

Interpreting Fault Codes:

If you find a code indicating a mechanical fault in the steering lock, it confirms the issue.

In this case, you might see codes like "Electronic steering lock has a malfunction with a mechanical fault" or "Electronic steering lock has a malfunction with an implausible signal.

Taking Action:

Based on the fault codes, it's recommended to replace the steering lock.

Ensure you disconnect the vehicle's battery before starting any work.

Addressing SRS Light (Airbag Warning):

If you remove the airbag during the steering lock replacement, you might trigger an SRS light.

After completing the job, use the diagnostic scanner to erase the SRS codes. Make sure the airbag connectors are securely plugged in before attempting this.

Post-Installation Checks:

Reconnect the battery and check for any lingering issues.

If all steps are followed correctly, the steering lock problem should be resolved, and any SRS light can be cleared with the diagnostic scanner.

By following these steps, you can diagnose and address the steering lock issue on your C300, saving you both time and money. See our ESL Emulator Fix-It kits here.

Happy DIY repairing!