Q: Overheating and heater not working

asked by on December 13, 2016

My vw passat is overheating and beeping saying check coolant level. Coolant levels are great but I have no heat and it's overheating. What could this be. Is it my thermostat? Cause I have coolant and I'm not leaking any I can only think of two of three possible things either it's my thermostat or my water pump but I'm not leaking so I canceled out the option of the water pump so I can only think of a sensor or my thermostat

My car's transmission is unknown to me.

It sounds like you may have a faulty thermostat as well as a bad coolant temperature sensor. If the coolant is not getting to the heater core, then this would indicate a bad thermostat or a clogged heater core not allowing warm coolant to pass through it. If it is a bad thermostat, this may explain both issues as the thermostat being stuck closed would cause the engine to overheat, which would also prevent warm coolant from getting to the heater core. I would start with checking and replacing the thermostat first since this may solve both problems. If this does not solve your issue, this may suggest a faulty coolant temp sensor causing the overheating reading and potentially a bad heater core causing your heating issue. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your car.

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