how to fix P0700 code in BMW 3 Series G20/G21 (2019-2024)

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the battery to prevent electrical shorts.

Tools Required:

• OBD-II scanner
• Socket set
• Torque wrench
• Multimeter
• Screwdrivers

2. Check and Replace Transmission Fluid

1. Locate the transmission fluid dipstick or fill plug.
2. Remove the dipstick or fill plug and check the fluid level.
3. If low, add the recommended transmission fluid (refer to the owner's manual for specifications).
4. If fluid is dirty, drain the transmission fluid and replace it with new fluid:
   • Place a drain pan under the transmission.
   • Remove the transmission pan bolts and carefully lower the pan.
   • Clean the pan and replace the filter (if applicable).
   • Reinstall the pan with a new gasket, torquing bolts to manufacturer's specifications.

3. Inspect and Repair Wiring/Connectors

1. Visually inspect the TCM wiring harness for any signs of damage or wear.
2. Use a multimeter to check continuity and resistance in the wiring.
3. Repair or replace any damaged wiring or connectors.

4. Test and Replace TCM (if necessary)

1. If no issues are found with fluid or wiring, use the OBD-II scanner to perform a functional test of the TCM.
2. If the TCM is not responding correctly:
   • Remove the TCM from its mounting location.
   • Disconnect the electrical connectors.
   • Install the new TCM by reversing the removal steps.
   • Ensure it is secured and properly connected.