how to fix Volkswagen Passat B8 (2015-2022) transmission slipping issue

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is on a flat surface and secure with wheel chocks.
• Disconnect the battery to avoid any electrical issues while working.

2. Fluid Replacement

a. Drain Transmission Fluid

• Locate the transmission drain plug (usually at the bottom of the transmission).
• Use a socket set to remove the drain plug and allow fluid to fully drain into a suitable container.
• Inspect the drain plug for metal shavings or debris; replace if necessary.

b. Replace Transmission Filter

• Remove the transmission pan by unscrewing the bolts with a socket set.
• Carefully detach the pan and replace the old transmission filter with a new one.
• Clean the pan and magnet before reinstallation.

c. Refill Transmission Fluid

• Reinstall the transmission pan with a new gasket, ensuring it is properly aligned.
• Tighten the pan bolts to the manufacturer’s torque specifications.
• Use a funnel to refill the transmission with the appropriate type and amount of transmission fluid, as specified in the owner’s manual.

3. Electrical Inspection

• Reconnect the battery and use a multimeter to check the voltage at the transmission solenoids.
• If voltage is absent or incorrect, inspect and repair the wiring or replace the solenoids as necessary.

4. Transmission Control Module (TCM) Reset

• If codes related to the TCM were found during diagnostics, reset the TCM using the OBD-II scanner.
• Follow up with a road test to ensure the transmission operates smoothly.