how to fix P0700 code in Toyota Highlander Fourth Generation (2020-present)

Solution

1. Preparation

• Gather tools and parts required.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Raise the vehicle securely on jack stands if accessing the underside.

2. Inspect and Replace Transmission Fluid

• Sub-steps:
  1. Remove the transmission fluid dipstick and check fluid condition.
  2. If fluid is dirty or low, drain the old fluid by removing the drain plug.
  3. Replace the fluid filter if applicable (access depends on model).
  4. Refill with new transmission fluid, adhering to Toyota specifications (typically Toyota ATF WS).
• Tools Required:
  • Socket set
  • Fluid pump
  • Drain pan

3. Repair or Replace Wiring and Connectors

• Sub-steps:
  1. Locate the TCM and inspect all associated wiring and connectors.
  2. Repair any frayed wires or corrosion found on connectors.
  3. If the connector is damaged beyond repair, replace it with an OEM part.
• Tools Required:
  • Wire stripper/crimper
  • Electrical tape
  • Multimeter

4. Reprogram or Replace TCM (if necessary)

• Sub-steps:
  1. If diagnostics indicate a faulty TCM, remove it from its housing.
  2. Install a new or repaired TCM, ensuring all connectors are secure.
  3. Use a scan tool to reprogram the TCM according to the manufacturer's specifications.
• Tools Required:
  • OBD-II scanner with programming capability
  • Socket set

5. Final Checks

• Reconnect the negative battery terminal.
• Clear any diagnostic trouble codes (DTCs) from the vehicle's computer.
• Test drive the vehicle to ensure the issue is resolved.