what does it mean if my Tesla Model S Original (2012-2020) shows a C1234 error code

Learn how to diagnose and fix C1234 brake issues in Tesla Model S (2012-2020). Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the parking brake is engaged.
• Disconnect the 12V battery for safety.

2. Inspect Brake Fluid and System

• Sub-steps:
  1. Open the hood and locate the brake fluid reservoir.
  2. Check fluid levels; top off with manufacturer-approved brake fluid if low.
  3. Inspect for visible leaks around brake lines and calipers.
  4. If leaks are found, replace damaged lines or calipers as necessary.

3. Check Brake Pedal and Switches

• Sub-steps:
  1. Remove the under-dash panel to access the brake pedal assembly.
  2. Inspect the brake pedal for proper movement and return.
  3. Test the brake switch operation by pressing the pedal and checking for continuity with a multimeter.
  4. Replace the brake switch if faulty.

4. Inspect ABS Module and Wheel Speed Sensors

• Sub-steps:
  1. Locate the ABS module, usually found near the master cylinder.
  2. Check for loose connections or damaged wiring.
  3. Inspect each wheel speed sensor; clean or replace if damaged.
  4. Reconnect all wiring securely.

5. Reconnect Battery and Clear Codes

• Sub-steps:
  1. Reconnect the 12V battery.
  2. Use the Tesla diagnostic software to clear the C1234 error code.
  3. Conduct a short test drive to ensure the issue is resolved.