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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is off.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect Transmission Fluid

• Tools Required: Dipstick, funnel, transmission fluid.
• Remove the transmission dipstick and check the fluid level.
• If low, add the appropriate type of transmission fluid as specified in the owner’s manual.
• Check fluid condition; if burnt or contaminated, flush the transmission.

3. Inspect Wiring and Connectors

• Tools Required: Visual inspection tools, multimeter.
• Remove any protective covers to access the wiring and connectors.
• Visually inspect for frayed wires or corrosion.
• Use a multimeter to test for continuity in the wires to the TCM.

4. Test Transmission Control Module

• Tools Required: OBD-II scanner or advanced diagnostic tool.
• Reconnect the battery and turn on the ignition without starting the engine.
• Use the scanner to check the TCM status and read any additional codes.
• If the TCM is faulty, follow the manufacturer's procedures for replacement.

5. Reconnect Battery and Test Drive

• Reconnect the negative battery terminal.
• Start the engine and check for any new codes.
• Take the vehicle for a test drive to ensure proper transmission operation.