my Volkswagen Golf MK7 (2015-2019) has a coolant warning light on, what should I do?

Solution

1. Preparation

• Gather tools and parts.
• Ensure the engine is cool before starting work.
• Disconnect the battery to prevent electrical issues.

2. Check and Refill Coolant

1. Open the hood and locate the coolant reservoir.
2. Remove the cap and check the coolant level; top off with the appropriate coolant type (G12 or G13 for VW).
3. If the coolant is low, inspect for leaks (refer to Diagnostic Steps).

3. Repair Leaks (if found)

1. Locate the Leak: Trace the coolant lines and inspect components like the water pump, radiator, and hoses.
2. Replace Damaged Parts:
   • If hoses are leaking, use a hose clamp tool to remove the damaged hose and replace it with a new one.
   • For radiator leaks, remove the radiator by unscrewing the mounting bolts and disconnecting the inlet and outlet hoses. Replace with a new radiator.
3. Seal Minor Leaks: Use a suitable radiator sealant if the leak is minor.

4. Replace Thermostat (if malfunctioning)

1. Drain the coolant from the system via the radiator drain plug.
2. Remove the thermostat housing by loosening the bolts with a socket set.
3. Replace the old thermostat with a new one, ensuring it is oriented correctly.
4. Reinstall the housing and torque bolts to manufacturer's specifications (typically around 10 Nm).

5. Refill Coolant and Bleed Air

1. Refill the system with the appropriate coolant mixture.
2. Run the engine with the radiator cap off to allow air to escape until the thermostat opens (watch for bubbles).
3. Recheck coolant level and top off as necessary.