Fans Constantly On

I have always noticed that the two fans on my GTO are always running, even when the car is first started cold. I was under the impression they were to kick on at a certain temp running at a certain percentage. I logged the DESIRED FAN SPEED and some other fan related parameters but they all read zero even when the car heated up.

Is this normal? Can it be adjusted in the tune via CMR?

[06MonteSS]

no, the only fan adjustments are the ones like you mentioned.. changing the % power at a given temp... have the same thing in CMR... can't change the temps, only the % fan power based on ECT...

Mine did the same thing when I updated to the latest CROM. Just have to modify the tune. In the Fan Control, there are temperature ranges and a percentage. That is what percentage the fan is spinning at. If you don't want them on that much, just set the percentage lower at the the lower temps. If you want to see what factory settings where, restore the factory tune, go into modify the factory tune and write down the factory settings. That will give you a baseline to start your adjustments from.

[06MonteSS]

stock fan settings for the gto are:

25% all the way up to 217F... then it's 49% for 221F and 225F, then 51% for 228F and 231F, then it finally goes to 91% for 239F to 250F...


look at the fan settings for the Monte!!
http://www.ls1tech.com/forums/attachmen ... 1212264487

For the beginning 192 range I have the fan set at 22%, IIRC. Does that mean 0-192 ECT the fan will run at 22%? I figured it kicked on at 192 ECT and running at 22%.

[06MonteSS]

no... it's as you figured...

when the temp hits 192, then the fan will kick on at 22% power.

[06MonteSS]

I have my fans set at

25, 50, 50, 75, 75, then 90 (or 95?) for all the rest on up...


and mine are not constantly on...


more than stock? yes...

but constantly? no...

06MonteSS wrote:

when the temp hits 192, then the fan will kick on at 22% power.

Hmmm, then it goes back to my original inquiry. Why do the fans run when the car is under 192 ECT? Morning cold start with ECT at ambient temp, the fans still run, both of them.

[06MonteSS]

hmmm.. . dunno man... that is interesting...

as I mentioned above, mine don't run all the time... I hear them turn on and off...

Can anyone from DS support help out for the reason why both fans in my GTO run constantly regardless of temp?

Is there a way to fix it with the CMR?

[mikel]

Have you tried setting them back to the way they are in the stock tune?

[06MonteSS]

are you running the stock t-stat, or a colder 160* one?? may be the issue...

tap into any wiring for aftermarket stuff you wired up??

have you tried restoring the original backup tune to your car, and running it, see if the same thing happens??

that will tell ya if it's the tune or not...

Did Goatluver ever resolve this.
I too have this issue with my 05 GTO. Predator is slp7190, 9r01.
I checked the fan settings on the Bobcat 421 tune, at 192ect, setting was something like .08, but my fans run as soon as the motor is started.
Before Bobcat tune, fans would not run until ect got to 211. Not a big deal, car maintains 190 to 196 ect's, just thought is was strange.
Fans do not run when key is in the ON position, motor must be running for fans to turn.
Suggestions????

Smitty'sGTO wrote:

Did Goatluver ever resolve this. Fans do not run when key is in the ON position, motor must be running for fans to turn.

Not resolved. Lew checked the tune in the CMR software and all the settings are correct. Odd stuff.

[06MonteSS]

Goatluver.... do this...

put the first two fan settings down to 0% at 192* and 196* (or at least as low as it will go 0.xx% something), and put the third (199*) at 25%...

that should work for ya... I just made Smitty a custom tune this weekend with those settings, and he reported back that it looks like that did the trick for him... his are not running all the time now...

Lemme know...