Cooling fan strategy on a 2020 XT4

[Thermo1223]

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

Has to be a glitchy tstat or temp sensor. Full on might be a failsafe condition for overheating and perhaps the car is thinking just that. A lot of newer engines(this one included) use an electronic coolant flow control valve, not just a standard thermostat like days of yore. It is made to promote fast warm-up and more precise control of engine temp(emissions) but like anything with technology there will be bumps in the road.

 

[michaelluscher]

Has to be a glitchy tstat or temp sensor. Full on might be a failsafe condition for overheating and perhaps the car is thinking just that. A lot of newer engines(this one included) use an electronic coolant flow control valve, not just a standard thermostat like days of yore. It is made to promote fast warm-up and more precise control of engine temp(emissions) but like anything with technology there will be bumps in the road.

I thought GM might've learned after the POS cooling system on 1.4/1.8 Cruze and Sonic
I know those had rampant thermostat/water pump/water outlet issues
Guess these LSYs aren't much better 🤔
A shame, for a 50k luxury brand with only 13,122 on the clock

 

[michaelluscher]

Apparently LSYs can  overheat, due to thermostat issues
I now know what a CCV is, and I don't like it 😳

https://gmauthority.com/blog/2022/06/your-gm-vehicles-2-0l-lsy-engine-may-be-overheating-because-of-this-part/

 

[wtd]

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

This right here. I had a bad coolant temp sensor cause the cooling fan to run all of the time on an older GM four cylinder car.

 

[snarl]

Unplug the fan.

 

[thescreensavers]

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.

Is 97 considered modern my Jeep does this too

 

[SC Maintenance]

Is 97 considered modern my Jeep does this too

If it has an ECU its modern to me

 

[michaelluscher]

3+ weeks appointment wait, no loaners available
McGuire Cadillac in Woodbridge, NJ can go suck a lemon 😤
They've always sucked, but they seem to be getting worse
Why she keeps giving them the business I have no idea 🤔

 

[clinebarger]

Just about any DTC can make the fans stay on, Roar & be annoying in general. It's designed to be annoying to force you into a dealership service department. No different than Toyota/Lexus disabling traction control over a Catalyst Efficiency DTC.

I get a GM K2XX truck in every week for the cooling fans staying on, O2 Sensors & Thermostats are the main cause. And it's always the thermostat regulating BELOW temp.....Not above temp with a P0128.

 

[michaelluscher]

Just about any DTC can make the fans stay on, Roar & be annoying in general. It's designed to be annoying to force you into a dealership service department. No different than Toyota/Lexus disabling traction control over a Catalyst Efficiency DTC.

I get a GM K2XX truck in every week for the cooling fans staying on, O2 Sensors & Thermostats are the main cause. And it's always the thermostat regulating BELOW temp.....Not above temp with a P0128.

No CEL or warning messages
Maybe the code hasn't had enough drive cycles to mature?
I'm disappointed that I didn't think to scan it for codes
I'll dust off the Autel later, see what it has to say for itself

 

[another Todd]

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.

Most vehicles will turn on the AC (without any indicator inside the vehicle) when in defrost mode or recirculate mode to prevent high humidity and fogging of the windows.

 

[michaelluscher]

Left it cold unused for a day, on level ground
Cold start, 43° coolant temp, cooling fan on full blast
Is that coolant level low enough to maybe be causing this?
If I can happen across some Dexcool, I'll top off and see if that helps

 

[KrisZ]

Definitely not normal. I would get it scanned to see if there are any stored codes. It looks like a sensor issue.
If you get no traction from a dealer, I would try unplugging the usual suspects that may call for high rad fan myself, like the coolant temp. sensor, AC compressor, coolant level sensor, anything plugging in to the thermostat. Something is triggering this rad fan to run high and it’s not normal.

 

[michaelluscher]

We got nothing 😳

 

[KrisZ]

Is that a manufacturer level type scanner or generic?
Maybe disconnect the batter for a minute to reset the ECU? At this point you have nothing to lose.

 

[dishdude]

Top the coolant off.

 

[Greasymechtech]

When its cold, top off the coolant. Don't let the dealer top it off and send you on the way with nothing fixed.

If you did the basic troubleshooting, and vehicle is under warranty, time for appointment with dealer. Let them play with the sensors, pump, thermostats, bulletins,......

 

[CapitalTruck]

Try another GM dealer for a closer appointment. Same engine in Equinox and Terrain. Also, if you can get an appointment sooner I might NOT top off coolant, don’t mess up the scene of the crime.

 

[mk378]

Add some coolant. That is a basic maintenance issue, and the possibility that it is simply lack of coolant needs to be ruled out. It sounds like it will be some time before seeing the dealer, during that time watch the level to see if it is leaking out.

 

[michaelluscher]

A revelation, glad I fired up the Autel 🤔

So apparently it's been malfunctioning for quite a while, interesting 🤔
Ambient temps are 60° or so these days, so it's been warming up just fine, gets straight to 200 and pretty much stays there, no more constant on cooling fan

I guess I'll wait on a dealer appointment, and let it be their problem