how to fix P0700 code in my Toyota Highlander Third Generation (2014-2019)

Solution

1. Preparation

• Gather all necessary tools and components.
• Disconnect the battery to ensure safety while working on electrical components.

2. Inspect and Replace Transmission Fluid

• Tools Required: Transmission fluid funnel, pan, and drain plug socket.
• Sub-steps:
  1. Place a drain pan under the transmission.
  2. Remove the drain plug and allow the old fluid to completely drain.
  3. Inspect the old fluid for metal shavings or burning smell.
  4. Replace the drain plug and refill the transmission with the manufacturer-recommended fluid type (usually Toyota ATF WS).
  5. Start the engine and let it idle; check the fluid level and add more fluid as necessary.

3. Check and Repair Wiring/Connections

• Tools Required: Multimeter, wire stripper/crimper.
• Sub-steps:
  1. Inspect the wiring harness and connectors to the transmission control module for any frays or corrosion.
  2. Use a multimeter to check for continuity in the wiring.
  3. Repair or replace any damaged wiring or connectors as needed.

4. Replace Transmission Control Module (if necessary)

• Tools Required: Socket set, torque wrench.
• Sub-steps:
  1. Locate the transmission control module (often found near the transmission).
  2. Disconnect the wiring harness from the module.
  3. Unbolt the transmission control module and remove it.
  4. Install the new module and secure it with bolts to the specified torque value.
  5. Reconnect the wiring harness to the new module.

5. Reset the Engine Control Module

• Sub-steps:
  1. Reconnect the battery.
  2. Use the OBD-II scanner to clear the P0700 code.
  3. Start the engine and allow it to reach operating temperature, checking for any new codes.