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

Solution

1. Preparation

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

2. Address Fluid Issues

• Check Fluid Level and Condition:
  • Remove the transmission dipstick, wipe clean, reinsert, and check fluid level.
  • If low, add the recommended ATF (Automatic Transmission Fluid) as specified in the owner’s manual.
  • If the fluid is dark or smells burnt, consider a transmission fluid change.

3. Replace Faulty Sensors

• Input/Output Speed Sensors:
  • Locate the sensors on the transmission.
  • Disconnect the electrical connector.
  • Remove the retaining bolts and take out the sensor.
  • Install the new sensor and reconnect the electrical connector.
  • Torque the bolts to manufacturer specifications.

4. Reprogram TCM (if necessary)

• If the TCM requires reprogramming due to software issues:
  • Use a BMW-specific diagnostic tool (e.g., ISTA or INPA) to perform the reprogramming.
  • Follow the on-screen instructions to complete the process.

5. Reconnect Battery and Test Drive

• Reconnect the battery and clear any error codes using the OBD-II scanner.
• Conduct a test drive to ensure the transmission operates smoothly.