smell something burn when turning on heat

I guess you have a new car, because your profile says it is a 2009 Prius. How long do you have it? Was this one of the first times you used the heat? If so, it could be just some residues burning out. I doubt you are out engine of coolant if the car behaves properly otherwise.

Was the smell strong? Was it persistent? Did you try to turn the heat back on ever since?

If the problem persists and you are unsure what is going on, you better see a mechanic.

 

1. Prius has two electric heaters that supplement the heater core. The heater core provides cabin heat from hot engine coolant. If the heater had not been used for a while, the electric heaters might emit odor until residue on the heating coils burns off, as previously mentioned.

2. It is not a good idea to rely solely on your "service person", and remain ignorant of basic owner responsibilities such as checking coolant and engine oil level. This should be done each time or every other time you buy gasoline. Why?

a) the tech may make a mistake.

b) your car might develop a leak between service intervals and if you don't figure that out and take immediate action, the car may be damaged to the point where a 4 or 5 figure repair bill will be incurred. Then you'll have to argue with your dealer about whether the repair should be covered under warranty, and that will be an unpleasant conversation.

Open the hood, and look for a translucent plastic reservoir behind the radiator. That is the engine coolant reservoir. You should see pink fluid in the reservoir and the level should be at or just below the line engraved into the reservoir that indicates full level.

Then look for another translucent reservoir mounted to the inverter. That is the inverter coolant reservoir, and a full mark is also provided for reference.

If your car needs coolant, buy a gallon container of pink Toyota Super Long Life Coolant from your dealer. This is already premixed with distilled water, so just pour in as needed to replenish.

 

I'll second the electric heater smell. That's my first guess, but to be safe, check the coolant levels as suggested.

Tom

 

FYI The owner's manual has good illustrations/drawings on various fluid reservoirs. It is really very easy to check the levels. Good luck!

 

I have noticed this smell occasionally when the blower fan is on. Can the electric heater be disabled to confirm this as the source of the smell? ....Tortus

 

If you really want to disable the electric heater, you could pull two 30A fuses which are labeled PTC HTR1 and PTC HTR2, as well as the 50A PS HTR fuse, all located in the main relay/fuse box next to the inverter.