Hard shifting Audi A6 C7

Diagnosing and Repairing Hard Shifting in an Audi A6 C7 (2011-2018)

When an Audi A6 C7 experiences hard shifting, the problem could stem from various components within the transmission system. Below, I provide a detailed guide for diagnosing and potentially repairing this issue.

Tools Required

• OBD-II Scanner
• Torque Wrench
• Transmission Fluid Funnel
• Drain Pan
• Socket Set
• Screwdrivers
• Diagnostic Software (VCDS for Audi)
• Jack and Jack Stands

Step 1: Check for Diagnostic Trouble Codes (DTCs)

1. Connect the OBD-II Scanner:
   • Plug the scanner into the vehicle's OBD-II port, located under the dashboard.
2. Scan for Codes:
   • Check for any transmission-related codes (e.g., P0700 series).
   • Note any codes and clear them to see if they return after a test drive.

Step 2: Inspect Transmission Fluid Level and Condition

1. Warm Up the Vehicle:
   • Drive the car for about 10-15 minutes to bring the transmission to operating temperature.
2. Lift the Vehicle:
   • Safely lift and support the vehicle using a jack and jack stands.
3. Check Fluid Level:
   • Locate the transmission fluid fill plug and remove it.
   • Ensure the vehicle is level and check if the fluid is at the correct level.
4. Inspect Fluid Condition:
   • If the fluid is dark or has a burnt smell, it may need replacement.

Step 3: Perform a Transmission Adaptation Reset

1. Use Diagnostic Software (VCDS):
   • With the ignition on, connect VCDS to the vehicle.
   • Navigate to the transmission control module.
   • Perform an adaptation reset to re-calibrate shifting.

Repair Instructions

Option 1: Transmission Fluid and Filter Change

1. Drain Old Transmission Fluid:
   • Place a drain pan under the transmission pan.
   • Remove the drain plug and allow the fluid to drain completely.
2. Remove Transmission Pan:
   • Unscrew the bolts securing the transmission pan.
   • Carefully remove the pan and clean the mating surfaces.
3. Replace Filter:
   • Remove the old transmission filter and replace it with a new one.
   • Ensure proper fitment by comparing the new filter with the old one.
4. Install Transmission Pan:
   • Reattach the transmission pan with a new gasket.
   • Torque bolts to the manufacturer's specifications using a torque wrench.
5. Refill Transmission Fluid:
   • Use the specified Audi transmission fluid.
   • Fill through the fill plug until fluid begins to trickle out.
6. Test Drive:
   • Lower the vehicle and perform a test drive.
   • Monitor shifting behavior and check for leaks.

Option 2: Addressing Solenoid or Mechatronic Issues

1. Inspect Solenoids and Mechatronic Unit:
   • If fluid change doesn't resolve the issue, the transmission solenoids or mechatronic unit may be defective.
2. Remove Mechatronic Unit:
   • Disconnect electrical connectors and remove securing bolts.
   • Carefully extract the unit from the transmission.
3. Test Solenoids:
   • Use a multimeter to check solenoid resistance. Refer to service manual for specifications.
   • Replace faulty solenoids.
4. Reinstall Mechatronic Unit:
   • Ensure a clean and secure installation.
   • Reconnect all electrical connections.

Conclusion

If hard shifting persists after performing these steps, further diagnosis by a professional may be necessary, potentially involving transmission teardown and inspection. Additionally, always refer to the vehicle's service manual for specific torque settings and procedures.