how to fix P0700 transmission code on BMW 3 Series E90/E91 (2005-2012)

Solution

1. Preparation

• Gather tools and parts required for repairs.
• Ensure the vehicle is on a level surface and secure it using wheel chocks.
• Disconnect the battery to prevent electrical shorts.

2. Check Transmission Fluid

• Tools Required: Transmission fluid dipstick, funnel.
• Remove the transmission dipstick (if applicable) and check fluid level.
• If fluid is low, add the appropriate type of transmission fluid (consult the owner’s manual for specifications).
• If fluid is burnt or contaminated, proceed to fluid replacement.

3. Replace Transmission Fluid and Filter

• Tools Required: Wrench set, socket set, transmission fluid pump, fluid container.
• Remove the transmission pan using a socket set.
• Carefully take out the old filter and replace it with a new one.
• Clean the pan and magnet (if equipped) to remove debris.
• Reinstall the pan with a new gasket and torque to manufacturer specifications.
• Use a fluid pump to fill the transmission with the correct amount of new transmission fluid through the dipstick tube.

4. Inspect and Repair Wiring/Connectors

• Tools Required: Multimeter, wire strippers, soldering kit (if necessary).
• Inspect wiring harnesses for any signs of wear, corrosion, or damage.
• Use a multimeter to test for continuity and resistance in the wires.
• Repair or replace damaged connectors or wiring as necessary.

5. Replace Transmission Control Module (if needed)

• Tools Required: Socket set, screwdriver set.
• If the transmission control module is faulty, locate it (typically found under the hood or near the transmission).
• Disconnect the electrical connectors and remove the module using a socket set.
• Install the new module, reconnect the wiring, and ensure it is properly secured.