how to fix P0700 code in Toyota Highlander XU70 (2020-Present)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to ensure safety.
• Lift the vehicle securely using jack stands if necessary.

2. Inspect and Replace Transmission Fluid

• Sub-steps:
  1. Locate the transmission fluid dipstick or fill plug.
  2. Remove the dipstick or fill plug and check fluid level.
  3. If the fluid level is low, add the manufacturer-recommended transmission fluid.
  4. If the fluid is contaminated or burnt, drain the old fluid using a fluid pump or by removing the drain plug.
  5. Replace with new transmission fluid, ensuring it meets OEM specifications.

3. Check and Repair Wiring/Connectors

• Sub-steps:
  1. Inspect the wiring harness leading to the TCM for any visible damage.
  2. Use a multimeter to test continuity and resistance in the wires.
  3. Repair or replace any damaged wires or connectors.
  4. Ensure all connections are secure and free of corrosion.

4. Test and Replace TCM (if necessary)

• Sub-steps:
  1. If diagnostics indicate a faulty TCM, remove it from its mounting.
  2. Disconnect the electrical connectors from the TCM.
  3. Install the new TCM by reversing the removal steps, ensuring connections are secure.
  4. Reconnect the negative battery terminal.

5. Clear Codes and Test Drive

• Sub-steps:
  1. Use the OBD-II scanner to clear the P0700 code and any related codes.
  2. Perform a test drive to ensure the transmission is operating properly and the check engine light remains off.