Positive Temperature Coefficient Heater? 2015 200 (1 Viewer)

[linuxgod]

To me it makes sense...because if you have TIME to let it adjust to a lower temp, you likely also have time to let it warm up.

But when you DON'T have to to wait, and are jumping in the car immediately? -It's perfect...because you NEED it more, and are also right there to adjust it down from High as soon as it's comfortable.

I'm betting Toyota doesn't automatically turn this on for fuel efficiency reasons. I'm not sure precisely how the EPA (or equivalent in other countries) tests emissions and MPG, but I suspect if the electric heat comes on automatically it increases pollutants and decreases MPG but if you have to specifically turn it on (i.e. through a button like the steering wheel heater or by setting the temp to max warm) then it's not part of the test cycle.

 

[mark71]

I'm betting Toyota doesn't automatically turn this on for fuel efficiency reasons. I'm not sure precisely how the EPA (or equivalent in other countries) tests emissions and MPG, but I suspect if the electric heat comes on automatically it increases pollutants and decreases MPG but if you have to specifically turn it on (i.e. through a button like the steering wheel heater or by setting the temp to max warm) then it's not part of the test cycle.

You are probably correct.

I am still surprised that this wasn't ever mentioned in the owner's manual. Tried it last night...awesome!

 

[Narkhelek]

PTC would have no impact on MPG as it's purely an electrical system.

Came across this in the repair manual related to the neural network control of the air conditioning system:

Neural Network Control:
-In previous automatic air conditioning systems, the air conditioning amplifier assembly determined the required outlet air temperature and blower air volume in accordance with the calculation formula that has been obtained based on information received from the sensors. However, because the senses of a person are rather complex, a given temperature is sensed differently, depending on the environment in which the person is situated. For example, a given amount of solar radiation can feel comfortably warm in a cold climate, or extremely uncomfortable in a hot climate. Therefore, as a technique for effecting a higher level of control, a neural network is used in the automatic air conditioning system. With this technique, the data that has been collected under varying environmental conditions is stored in the air conditioning amplifier assembly. The air conditioning amplifier assembly can then effect control to provide enhanced air conditioning comfort.
-The neural network control consists of neurons in the input layer, intermediate layer, and output layer. The input layer neurons process the input data of the ambient temperature, the amount of sunlight, and the room temperature based on the outputs of the switches and sensors, and output them to the intermediate layer neurons. Based on this data, the intermediate layer neurons adjust the strength of the links among the neurons. The sum of these is then calculated by the output layer neurons in the form of the required outlet temperature, solar correction, target airflow volume, and outlet mode control volume. Accordingly, the air conditioning amplifier assembly controls the servo motors and blower motor in accordance with the control volumes that have been calculated by the neural network control.

Kind of creepy as it makes it sound like there is a little tiny brain controlling everything.

 

[Narkhelek]

On my 2009 I've figured out that I don't actually need to adjust the temperature setting to HI to activate the PTC. I only have to manually turn the blower on which is nice to not have to hit the temp button a dozen times. One less thing I have to manually mess with although I still think the whole system should be automatic.

 

[teambell]

On my 2009 I've figured out that I don't actually need to adjust the temperature setting to HI to activate the PTC. I only have to manually turn the blower on which is nice to not have to hit the temp button a dozen times. One less thing I have to manually mess with although I still think the whole system should be automatic.

Help me understand your process, you just hit the <climate> button and then what?

 

[Narkhelek]

Hit the climate button then set the blower speed to anything although I usually just set it to max fan speed. It works regardless if you have the air director set to floor, mixed, or dash. I'm guessing that when the service manual stated the temp has to be set to HI is wasn't actually talking about the user set temp but what the climate system determined the temp setting needs to be based on the environmental conditions which would be HI if it was cold enough to warrant using the PTC.

It's really nice not to have hit the temp button a bunch of times to HI then a bunch more to set it back to the temp I actually want. I've done this the last couple mornings when the temp was below freezing and I start to feel warmth in about 30-45 seconds.

 

[teambell]

Thanks - will try that.

 

[Markuson]

Old thread...but this is an example of the extra though and effort Toyota puts into the LC. Not an advertised feature....but just like the massively high quality welds & beef underneath that salesman don’t know about...it’s there. Land Cruiser isn’t perfect (no such thing) but they clearly do try to add things like this where they would skip it elsewhere.

 

[04UZJ100]

Old thread...but this is an example of the extra though and effort Toyota puts into the LC. Not an advertised feature....but just like the massively high quality welds & beef underneath that salesman don’t know about...it’s there. Land Cruiser isn’t perfect (no such thing) but they clearly do try to add things like this where they would skip it elsewhere.

Don’t forget about the cool box too!!

 

[bloc]

Bumping this thread for new people that didn’t know about the feature.

Currently on a ski roadtrip so I’ll be giving it a try finally.

 

[04UZJ100]

I don’t seem to notice or have it on my 2020…..was 5F and vents never felt warm until the engine/thermostat opened…..

 

[linuxgod]

Manually set vents to windshield defroster

Turn temp to Hi

I do not find the PTC heats up instantly. Typically within ~2 minutes the air coming out is luke warm. it will get hot for me around the time the engine just starts to move off the Cold line in the temp gauge, but that can take a few more minutes. You might be able to optimize the warm up speed by adjusting the fan speed to low at first... if you leave it on Auto it will run on full speed which makes the air feel cooler of course.

 

[04UZJ100]

Manually set vents to windshield defroster

Turn temp to Hi

I do not find the PTC heats up instantly. Typically within ~2 minutes the air coming out is luke warm. it will get hot for me around the time the engine just starts to move off the Cold line in the temp gauge, but that can take a few more minutes. You might be able to optimize the warm up speed by adjusting the fan speed to low at first... if you leave it on Auto it will run on full speed which makes the air feel cooler of course.

Will try that next time

 

[bloc]

It may not allow the PTC heater at lower fan speeds to prevent it overheating. Might need the significant air flow to function correctly. I’ve been to a couple mild furnace fires where the fan stopped running but the electric grid heater stayed on eventually igniting the duct insulation near it via radiant heat.

I intend to experiment with it over the next couple days.. should be less than 10F the next couple mornings where I’ll be.

 

[andyp]

Had no idea this was there.

So set temp to max and fan to max. I'll give it a try.

 

[scottm]

3 hour stop at O'Hare, then Dallas, home to O'Hare tomorrow afternoon. This thread is timely, snowstorm warning for tonight and tomorrow. Hour long effort riding buses out to my car to crank the heat and see if this works. Should I have switched to defrost? I'll find out tomorrow night if this works.
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Plow trucks are lining up. Hopefully I get out of here before the snow hits
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[linuxgod]

3 hour stop at O'Hare, then Dallas, home to O'Hare tomorrow afternoon. This thread is timely, snowstorm warning for tonight and tomorrow. Hour long effort riding buses out to my car to crank the heat and see if this works. Should I have switched to defrost? I'll find out tomorrow night if this works.
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View attachment 2911287View attachment 2911288
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Plow trucks are lining up. Hopefully I get out of here before the snow hits
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View attachment 2911290

If you were planning to remote start it, then yes you should've switched to defrost. The PTC is only in the defroster near the windshield and to my knowledge won't operate in other positions.

 

[linuxgod]

 

[scottm]

If you were planning to remote start it, then yes you should've switched to defrost. The PTC is only in the defroster near the windshield and to my knowledge won't operate in other positions.

The vent selection is still in auto, should go to windshield at 18F tomorrow. The good thing is I can press the defrost button without waiting for the touch screen to finish warning me about every hazard

 

[andyp]

So will this ever activate with everything set to AUTO?