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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Ensure the vehicle is on a flat surface and securely raised if needed for access.

2. Inspect and Replace Transmission Fluid

• Sub-steps:
  1. Locate the transmission dipstick and remove it.
  2. Check the fluid level; if low, add the manufacturer-recommended transmission fluid.
  3. If the fluid is dark or contains debris, proceed to drain and replace it.
  4. To drain, remove the transmission pan bolts and carefully lower the pan.
  5. Allow the old fluid to completely drain, then replace the filter if applicable.
  6. Reinstall the transmission pan with a new gasket and torque bolts to the specified value (typically around 8-10 ft-lbs).

3. Repair or Replace TCM

• Sub-steps:
  1. Remove any components obstructing access to the TCM (if necessary).
  2. Disconnect the harness from the TCM and inspect for any visible damage.
  3. If the TCM is faulty, replace it with a new unit specific to the 2020-present Highlander.
  4. Reconnect the harness and any components that were removed.
  5. Reconnect the battery terminal.

4. Clear Codes and Test Drive

• Sub-steps:
  1. Use the OBD-II scanner to clear the P0700 code from the vehicle’s memory.
  2. Start the engine and allow it to idle for a few minutes.
  3. Perform a test drive under various conditions to ensure shifting is smooth and the check engine light remains off.