Checking the water flow

HINT: The overheating thermostat cuts out at 120 °C. 

Check if the lines to and from the heater are blocked, or if the heater is damaged causing the through flow to be restricted in some way.

Remedy as necessary.

Was a fault detected? 

• YES 

  Refer to Verification 

• NO 

  Refer to Checking the engine coolant temperature sensor