Heat NOT working, ONLY works on HI setting

[Hammerle9]

2013 Hybrid with 98k. It blows out warm air only on HI setting. This is the same in electric or gas mode.

If I lower the temperature to 85 or below, the temperature of the air coming out is drastically cooler.

Any suggestions?

Thank you

[lolder]

How does it work in "Auto" with temperature set in the '70's?

[Hammerle9]

How does it work in "Auto" with temperature set in the '70's?

It blows cold. It is not warm at all, maybe same as outside air temp?

Fan speed adjusts up and down normally.

[billford]

As a starting point, make sure the engine coolant is full.

[Hammerle9]

As a starting point, make sure the engine coolant is full.

Just checked. It might be 2-3 ounces low. I will top off tomorrow and check again.

 

My wife also said that it doesn't make a sounds when pushing the auto button. It will make the noise when selecting it from the touch screen, but NOT when selecting the Auto button below. None of the other buttons make a sound also(defrost, rear defrost, etc.) Not sure if this is related.

Edited October 10, 2017 by Hammerle9

[lolder]

I think there is an electric pump that circulates engine coolant to the heater core. How long have you owned the car?

Edited October 10, 2017 by lolder

[Hammerle9]

I think there is an electric pump that circulates engine coolant to the heater core. How long have you owned the car?

We have owned it since new. We currently have 98k on it.

 

Is there a way to check this? Why would it work when placed on HI setting?

[lolder]

I don't know. It's computer controlled like everything else. You can try a hard reset by disconnecting the negative terminal of the 12 vdc battery for about 5 minutes if you know how to do that. Otherwise it's off to the dealer.

[Hammerle9]

I pulled the negative terminal and left it off for about 20 minutes. It did give me the sound on the buttons back. I did NOT have a chance to road test it...but I think it might have worked.

[Hammerle9]

I don't know. It's computer controlled like everything else. You can try a hard reset by disconnecting the negative terminal of the 12 vdc battery for about 5 minutes if you know how to do that. Otherwise it's off to the dealer.

Road tested it today and we have HEAT again!

 

Hip Hip Hooray!!!!

 

THANK YOU SOOOoooo MUCH!

[tinmandmc]

Thank you very, VERY much for posting this. Saved my day! I had the same problem, No heat except when on "HI." The same solution, turn car off, take negative terminal off battery for a few minutes, put terminal back on, restart. It worked!

 

Thanks again.

[billford]

Thank you very, VERY much for posting this. Saved my day! I had the same problem, No heat except when on "HI." The same solution, turn car off, take negative terminal off battery for a few minutes, put terminal back on, restart. It worked!

 

Thanks again.

 

I had the same problem few years ago. Disconnecting the battery did fix it at the time.

There is a software reflash to update the FCIM (heating system) to fix it permanently. Its been available from 2015. If it happens again, good idea to get it done.

[bferguson001]

Dec 30th, 2023 same thing happened with my car, a 2016 Hybrid. While I was driving it went from warm air to cold except on HI. The hard reset by disconnecting the battery worked for me.

Brian

[MeeLee]

On high you probably will be using the battery (electric heater).

 

Disconnect the battery sounds like an error that could happen due to low battery voltage.

Try swapping out for a Lithium battery of the same size, and at least 36AH (maybe 50 if you're in colder regions).