how to fix B1242 code in Tesla Model S Original (2012-2020)

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, basic hand tools (screwdrivers, socket set), torque wrench.
• Disconnect the vehicle's 12V battery to ensure safety while working on the airbag system.
• Allow the vehicle to sit for at least 10 minutes to discharge any residual charge in the airbag system.

2. Inspect and Repair Wiring

• Sub-steps:
  1. Remove the passenger seat from the vehicle by unscrewing the mounting bolts and disconnecting the electrical connectors underneath.
  2. Examine the wiring harness connected to the passenger seat occupancy sensor for any frays, exposed wires, or loose connections.
  3. If damage is found, repair or replace the affected wiring and connectors.
  4. Reconnect the seat occupancy sensor and ensure a secure connection.

3. Replace Passenger Airbag Module (if necessary)

• Sub-steps:
  1. If the passenger airbag module is determined to be faulty during diagnostics, carefully detach the airbag module from its mounting.
  2. Disconnect the wiring harness from the airbag module.
  3. Install the new airbag module by connecting the wiring harness and securing it in place following the manufacturer's torque specifications (typically around 7-10 Nm).
  4. Double-check all connections and ensure everything is properly secured.

4. Reinstallation and Testing

• Sub-steps:
  1. Reinstall the passenger seat, ensuring all mounting bolts are tightened to the manufacturer's specifications (typically around 20-30 Nm).
  2. Reconnect the vehicle’s 12V battery.
  3. Use the OBD-II scanner to clear all fault codes and perform a system check to ensure the B1242 code does not reappear.