Cooling fan strategy on a 2020 XT4

Joined
Oct 7, 2012
Messages
5,365
Location
Staten Island, NY
What the hell is GM doing?
Or is it just broken?
It's gotten cold here in NYC, and I'm noticing our 2020 XT4 takes longer than I'd like for it to heat up
Remote starting doesn't give it the head start it should, and turning the heat on sends the coolant temp gauge plummeting
It will eventually get to 190°+, even on the highway and hold it
But it could take an hour +
I noticed sitting in it a minute or two after cold start (HVAC system off), the cooling fan is screaming 🤷‍♂️
I could see the cooling fan coming on and off if I had defrost on, and the A/C compressor was coming on and off
But HVAC off, 2-3 minutes into the cold start, I see no need for the cooling fan to be on
It's on at times I feel it shouldn't be, it almost seems stuck on

It's got a laundry list of other little things that need addressed, so it'll be off to the dealer soon
I'm just curious 🧐
 
The AC used to come on in my 2020 Equinox even if it was turned “off” and using settings other than defrost. The ac/compressor has its own algorithm and usage matrix. I could never figure it out.
 
The AC used to come on in my 2020 Equinox even if it was turned “off” and using settings other than defrost. The ac/compressor has its own algorithm and usage matrix. I could never figure it out.
Most modern cars have a dehumidification cycle that uses the AC to get the moisture out of your interior air even when its not in cooling mode. How / when is still a good question? I would love to see the cycle algorithm explained.
 
Well the car is never fully going to get to temp just idling along on a remote start. Remote start is tied to defrost and I know that for a fact on my truck. Doesn't matter if it's 15F or 55F is auto starts in defrost mode. I mean consequently with a working thermostat it wouldn't matter if the fans are on or not.
 
TSB below. Not pictured: Anything between Cold (below 50) and Hot (above 59) reverts to last known setting.
5256D14E-AC5C-417B-B0E4-033E4A4D32E1.png
 
Yeah that doesn't seem right on a cold start w/ all HVAC functionality turned off.

I know our 2019 Nissan Pathfinder will run the cooling fans at low speed with any HVAC setting, even on a -10degF cold start. With all HVAC function off, it will not run the fans. If you use remote start, it automatically puts the w/s defrost on full speed and runs the cooling fans at a higher speed as well. Super annoying.
 
Looking at the map, it looks like there's about a 3 hour drive from Staten Island NY to State College Pennsylvania. Save that option for last if the dealer can't fix it.
While I would like to plan a visit to see Ivan, it's a lease and still under warranty
I do now think something's wrong with it
I drove it all day today, cooling fan on full blast, which really blunts the heating performance
Coolant level looks ok
I called McGuire, service is open tomorrow, they can work on it into the new year, I'll probably have a 3 page R.O by the time I'm through
 
While I would like to plan a visit to see Ivan, it's a lease and still under warranty
I do now think something's wrong with it
I drove it all day today, cooling fan on full blast, which really blunts the heating performance
Coolant level looks ok
I called McGuire, service is open tomorrow, they can work on it into the new year, I'll probably have a 3 page R.O by the time I'm through
Keep us in the loop, got my curious.
 
At highway speed, it doesn't matter if the fans are on or not. This sounds like the thermostat is stuck partway open, about the only reason for slow to warm up. There is also a "slow to warm up" code which should be being set and turn on the CEL here.
 
At highway speed, it doesn't matter if the fans are on or not. This sounds like the thermostat is stuck partway open, about the only reason for slow to warm up. There is also a "slow to warm up" code which should be being set and turn on the CEL here.
Yeah, my Tundra radiator fan runs 100% of the time proportional to engine RPM even at -10F so I can't imagine even a wonky radiator fan would be enough to cause the problem noted by the OP.
 
At highway speed, it doesn't matter if the fans are on or not. This sounds like the thermostat is stuck partway open, about the only reason for slow to warm up. There is also a "slow to warm up" code which should be being set and turn on the CEL here.
Would it make more of a difference in low speed stop and go?
Even with a properly functioning cooling system, the cooling fan stuck on high from cold start seems like it would really slow down warmup/prevent getting up to full temp?
 
Defective coolant temp sensor and or bad thermostat can cause erratic gauge and fans to run constant at times, sometimes no heat or AC. Disconnect battery for about 3-5 minutes and retry and see if it works. Sometimes its a temp fix but it may hold long enough till you get fixed,it sort of resets them for a while. Common problems on 3.6 LGX equipped vehicles. Don't know what is in a XT4
 
It's the 2.0T LSY
I've been using it all afternoon, around town and errands
Left it running for 5 minutes near the Halal cart
There's no reason for it not to be up to temp by now

I can't accept this as normal behavior, in 31° ambient
We'll see what the dealer says
No warning lights or messages, just constant fan and poor heat/warmup
 
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