how to fix Volkswagen Passat B8 (2015-2022) with low coolant level issue?

Solution

1. Preparation

• Gather necessary tools and parts.
• Park the vehicle on a level surface and allow the engine to cool completely.
• Disconnect the battery to avoid any electrical issues.

2. Inspect and Repair Leaks

• Coolant Reservoir:
  • Remove the coolant reservoir by unscrewing the mounting bolts.
  • Replace if cracked or damaged.
• Hoses:
  • Inspect all hoses connected to the cooling system.
  • Replace any damaged hoses with new ones.
• Radiator Inspection:
  • Check for leaks by visually inspecting the radiator.
  • If leaks are found, replace the radiator.
• Radiator Cap:
  • Remove the radiator cap and inspect the rubber seal for wear.
  • Replace if damaged to ensure proper sealing.

3. Refill Coolant

• Locate the coolant reservoir and ensure the correct coolant type is used (G13 or G12, as specified by Volkswagen).
• Mix coolant with distilled water as per manufacturer’s specifications (usually 50:50 mix).
• Pour the coolant mixture into the reservoir until it reaches the maximum fill line.

4. Bleed the Cooling System

• Start the engine and let it idle until it reaches operating temperature.
• Turn the heater to maximum and allow the engine to run for 10 minutes.
• Check for air bubbles in the coolant reservoir; if present, continue to run until they subside.
• Turn off the engine and allow it to cool, then top off the coolant if necessary.