how to fix delayed engagement in Tesla Model S Plaid/Refresh (2021-present) transmission?

Solution

1. Preparation

• Gather tools and parts necessary for the repair.
• Disconnect the 12V battery for safety.
• Ensure the vehicle is on a level surface and securely supported.

2. Check and Replace Transmission Fluid (if required)

• Tools Required: Fluid pump, torque wrench, socket set.
• Locate the transmission fluid fill plug.
• Using a fluid pump, extract the old transmission fluid if it is contaminated or low.
• Replace with OEM-approved transmission fluid. Ensure to fill to the specified level (check owner's manual for specifics).
• Reinstall the fill plug and torque to manufacturer specifications.

3. Update Transmission Control Module (if applicable)

• Tools Required: Laptop with appropriate software and USB cable.
• Connect the laptop to the vehicle’s diagnostic port using a USB cable.
• Open Tesla's diagnostic software and check for available updates for the TCM.
• Follow on-screen instructions to update the TCM software, if needed.

4. Inspect and Repair Wiring Connections

• Visually inspect the wiring harness leading to the TCM and transmission sensors for any fraying or damage.
• If damage is found, repair or replace the affected wiring.
• Ensure all connectors are securely fastened and free of corrosion.

5. Reconnect Battery and Test

• Reconnect the 12V battery.
• Start the vehicle and allow it to go through its initial checks.
• Test the transmission engagement by shifting from park to drive and reverse to confirm the issue is resolved.