my Volkswagen Passat B8 (2015-2022) heater is not working what can I check

Solution

1. Preparation

• Tools Required: Socket set, screwdriver set, OBD-II scanner, multimeter, coolant.
• Ensure the engine is cool and the vehicle is parked on a level surface.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Check and Refill Coolant

• Locate the coolant reservoir.
• If low, add the appropriate type of coolant (check owner's manual for specifications).
• Reconnect the battery terminal.

3. Inspect and Flush Heater Core

• Tools Required: Hose clamps, garden hose.
• Disconnect the inlet and outlet hoses from the heater core.
• Use a garden hose to flush the heater core in both directions until clear water flows out.
• Reconnect hoses and ensure they are secured with clamps.

4. Replace Thermostat (if faulty)

• Drain the engine coolant to a safe level.
• Remove the thermostat housing by unscrewing the bolts.
• Replace the thermostat with a new one, ensuring proper orientation.
• Reinstall the thermostat housing and torque to manufacturer specifications (usually around 10-15 Nm).
• Refill the cooling system with the correct coolant.

5. Test Blower Motor

• Tools Required: Multimeter.
• Connect the multimeter to the blower motor connector.
• Turn the ignition on and test for voltage at the blower motor.
• If no voltage is present, check the fuses and relays associated with the HVAC system.
• Replace the blower motor if it is not functioning properly.