how to fix P0700 transmission control system malfunction in Honda Civic 10th Generation (2016-2021)

Solution

1. Preparation

• Gather tools and materials.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Ensure the vehicle is on a level surface and securely raised if needed.

2. Inspect and Replace Transmission Fluid

• Tools Required: Socket set, fluid pump, container for old fluid.
• Check the transmission fluid level using the dipstick. If low, add the recommended fluid type (Honda ATF DW-1).
• If the fluid is discolored or burnt, drain the old fluid into a container, replace the transmission filter, and refill with fresh Honda ATF DW-1.

3. Inspect and Repair Wiring/Connectors

• Tools Required: Multimeter, wire brush, dielectric grease.
• Visually inspect the wiring and connectors for damage or corrosion.
• Use a multimeter to test the continuity of wires. Repair or replace any damaged wiring.
• Clean connectors with a wire brush and apply dielectric grease to prevent future corrosion.

4. Test and Replace the TCM (if necessary)

• Tools Required: OBD-II scanner, socket set.
• If the TCM is suspected to be faulty, replace it. Remove the old TCM by unscrewing the mounting bolts and disconnecting the wiring harness.
• Install the new TCM by reversing the removal steps and ensuring it is properly connected.

5. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0700 code and any other related codes.
• Conduct a test drive to confirm that all systems are functioning correctly.