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Discussion Starter #1
I'm noticing 2 issues on my new to me 2018 and looking for verification that this is normal?

1. I'm noticing that when the climate control is in Auto mote- the A/C light is on all the time, regardless of if it is 70 degrees or 30 degrees outside. Is this normal? On my LMM the A/C would not come on under a certain temp in auto mode.

2. When using remote start and the temp is below 40 but not yet to freezing, I'm noticing that the rear window defrost comes on automatically and stays on, even after key-on. Is this normal? This seems like a dangerous thing if the grid is coming on and staying on when there is no need for it to do so. It did not do this in my LMM as well.
 

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Both of those are normal. The rear defrost is needed for defogging as well. Auto has to have the ac light on because it will use the compressor as needed. Your front defrost will always turn on the compressor. It is also for “drying” the air.
 
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Both of those are normal. The rear defrost is needed for defogging as well. Auto has to have the ac light on because it will use the compressor as needed. Your front defrost will always turn on the compressor. It is also for “drying” the air.
This.
 

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As previously stated, normal operation. The rear defroster has an auto shutoff after 15 minutes or so when it's turned on manually or automatically, so no need to worry. It will also only do it below a certain temperature.
If you really want to, you can turn off the remote start auto rear defrost by going into your vehicle settings on the radio. I think it's "comfort and convenience" or something like that. I can get you the exact menu choices if you want.
I leave my setting on year round. It's extremely convenient at defrosting the truck even when it's just a heavy morning dew. Don't need to wipe the mirrors off assuming you have the heated mirrors as well.
Congrats on the new truck BTW.
 
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It's been normal for some time now for the A/C to be on when in Auto mode. I know it was always on in my LML.

And remote start mode will kick everything on to warm up when it's cold out, including the seat heat. Great feature IMO.
 

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The a/c compressor is not always on just because the led in the button is on. All the HVAC controls are telling you is that it MAY pull the compressor clutch in if all of the right conditions are present and it’s deemed necessary. That’s it. Mileage misers freak out about it. It IS possible to use the HVAC system in manual mode too, not the end of the world. 😄👍🏻
 
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Correct. My comment was kinda poorly stated. I meant the A/C was activated at all times, not actually turning all the time. That's why I never worried about it. It would cycle in as necessary. That said, most times I had the hood up, the compressor was cycling. Of course, I run in a lot of moderate temps, not so much in the bitter cold.
 

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Correct. My comment was kinda poorly stated. I meant the A/C was activated at all times, not actually turning all the time. That's why I never worried about it. It would cycle in as necessary. That said, most times I had the hood up, the compressor was cycling. Of course, I run in a lot of moderate temps, not so much in the bitter cold.
Not slamming your post at all and just pointing out that some customers come in seriously complaining about this exact topic (a/c) and freak out when you tell them to just select it off, putting the system in manual mode and then adjust the system to your preferred settings. That’s all. 👍🏻
 

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I have a 19 ...i wish the heated wheel activated with auto start
 

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Discussion Starter #11
Thanks. My concern was that the A/C was going to run all the time if the light was on which is what I did not want. Not because of economy, but because I simply do not need the AC on most of the time and would prefer to extend the life of the AC as much as possible and was worried that with it running all the time I'd be looking at new AC componants come 200,000 miles or so. As for the rear window defrost/defog- Again, I don't tend to need it often and would prefer to turn it on when I need it, not to have it auto come on just because the temp dropped below 40 yet there is nothing on the back windshield, moisture, fog, or frost that needs to be removed.
 
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