how to diagnose P0700 code in my Toyota Tacoma N300 (2016-Present)

Solution

1. Preparation

• Gather tools and materials needed for the repair.
• Disconnect the battery to prevent any electrical shorts.

2. Inspect and Replace Transmission Fluid

• Sub-steps:
  • Remove the transmission fluid dipstick and check the fluid level.
  • If the fluid is low or burnt, drain the old fluid using a fluid pump.
  • Replace the fluid with the manufacturer-recommended transmission fluid (e.g., Toyota Genuine ATF WS).
  • Refill the transmission fluid to the proper level, checking periodically with the dipstick.

Tools Required:

• Fluid pump
• Transmission fluid funnel
• Torque wrench

3. Inspect Wiring and Connectors

• Sub-steps:
  • Locate the transmission control module wiring harness.
  • Disconnect the harness and inspect for any signs of damage or corrosion.
  • Clean any corroded terminals with electrical cleaner.
  • Reconnect the harness securely.

Tools Required:

• Electrical cleaner
• Wire brush (if necessary)

4. Test Transmission Control Module (TCM)

• Sub-steps:
  • Using a multimeter, check the voltage at the TCM connector (should be within manufacturer specifications).
  • If voltage is not present, trace wiring back to battery and connections.
  • If the TCM is faulty, replace it with a new unit.

Tools Required:

• Multimeter