how to troubleshoot transmission slipping in Toyota Highlander XU70 (2020-Present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent any electrical shorts during the repair.

2. Check and Replace Transmission Fluid

• Tools Required: Transmission funnel, fluid catch pan.
• Sub-steps:
  1. Remove the transmission dipstick and check the fluid level.
  2. If fluid is low, add the recommended type of transmission fluid (Toyota ATF WS).
  3. If the fluid is burnt or contaminated, drain the transmission fluid using a catch pan.
  4. Replace with new fluid until reaching the correct level on the dipstick.

3. Inspect and Replace Transmission Filter

• Tools Required: Socket set, torque wrench.
• Sub-steps:
  1. Remove the transmission pan by loosening the bolts carefully.
  2. Replace the transmission filter with a new one; ensure the sealing surface is clean.
  3. Reinstall the transmission pan with a new gasket; torque bolts to manufacturer specifications.

4. Check and Replace Solenoids

• Tools Required: Socket set, multimeter.
• Sub-steps:
  1. Remove the transmission valve body to access the solenoids.
  2. Disconnect the electrical connectors from the solenoids.
  3. Test solenoid resistance with a multimeter; replace any that are outside the manufacturer's specifications.
  4. Reinstall the valve body and solenoids, ensuring all connections are secure.

5. Final Assembly and Reconnection

• Sub-steps:
  1. Reconnect the battery and ensure all tools are removed from the engine bay.
  2. Start the vehicle and allow it to reach operating temperature.