how to diagnose P0700 code on Tesla Model S Plaid/Refresh (2021-present)

Learn how to diagnose and fix P0700 transmission control system malfunction in Tesla Model S Plaid. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, torque wrench, socket set, transmission fluid.
• Ensure the vehicle is parked on a level surface and the parking brake is engaged.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect Transmission Fluid

• Remove the transmission fill plug.
• Check the fluid level using a dipstick or by feel; add fluid if low using the manufacturer-recommended transmission fluid.
• Inspect the fluid for signs of burning or contamination (dark color, burnt smell).

3. Repair Wiring and Connectors

• Inspect the wiring harness connected to the TCM for frays or breaks.
• Clean any corroded connectors with electrical contact cleaner and ensure a tight connection.
• If damaged, replace the wiring harness or connectors as needed.

4. Update Software

• Reconnect the vehicle to the Tesla service menu via an internet connection.
• Check for any available software updates that pertain to the transmission system.
• Follow on-screen instructions to update the software if needed.

5. Reset TCM

• After completing repairs and updates, reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0700 code from the memory.
• Start the vehicle and let it idle for a few minutes to allow the TCM to recalibrate.