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

Solution

1. Preparation

• Gather tools: OBD-II scanner, multimeter, socket set, torque wrench, transmission fluid, replacement solenoids (if needed).
• Ensure the vehicle is parked on a level surface and the engine is off before starting.

2. Address Transmission Fluid Issues

1. Check Fluid Level

   • Remove the transmission dipstick and wipe it clean.
   • Reinsert and remove again to check the level; add fluid if low.
   • If the fluid is dark or has a burnt smell, consider a fluid change.

2. Replace Fluid (if necessary)

   • Drain the old transmission fluid using a drain pan.
   • Remove the transmission pan using a socket set.
   • Clean the pan and replace the filter inside if applicable.
   • Reinstall the pan with new gasket and torque to manufacturer's specification.
   • Refill with new transmission fluid through the dipstick tube.

3. Inspect and Replace TCM or Solenoids

1. Inspect Wiring and Connectors

   • Visually check for any damaged wires or loose connectors.
   • Repair or replace any damaged components found.

2. Replace the TCM (if necessary)

   • Disconnect the negative battery terminal.
   • Locate the TCM, usually situated near the transmission.
   • Unplug the TCM connectors and remove any mounting bolts.
   • Install the new TCM and reconnect the wiring.

3. Replace Transmission Solenoids (if faulty)

   • Remove the transmission pan again if not previously done.
   • Locate and remove the solenoids using a socket set.
   • Install new solenoids and reassemble the transmission pan.