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Fan always running... SCT X3?

  • Thread starter Thread starter Blue89ELEX
  • Start date Start date Oct 2, 2009

Blue89ELEX

New Member
Jan 22, 2002
23
0
1
Oct 2, 2009
#1
  • Oct 2, 2009
  • #1
I just loaded in an SCT X3 "strategy" tune. Now, it seems like my fan is running all the time. I checked both of the engine/fan temperature settings inside the X3, and both seemed normal (don't remember exact, but fan low/high about 170*F/220*F)...

Still, the fan starts about 10 seconds after the engine starts, and runs until I turn the engine off. I thought it may be a bad sending unit, but my dash temp gauge seems to read normal...


Any suggestions? Thanks!
 

hotdog71

Member
Dec 8, 2004
427
0
16
Seattle, Eastside
Oct 2, 2009
#2
  • Oct 2, 2009
  • #2
So if you pull the tune dose it operate normally?

It seems odd my Diablo pred changes the fan set point by 10F I believe but it not on all the time.
 
J

Jbauer

New Member
Jan 20, 2008
506
0
0
Oct 2, 2009
#3
  • Oct 2, 2009
  • #3
maybe the relay got defective or something. That can happen when loading a tune since i think your actually suppose to unplug it..and no one does
 
T

tonytaylor85

Member
Sep 3, 2009
126
0
17
Augusta GA
Oct 3, 2009
#4
  • Oct 3, 2009
  • #4
The stock low speed fan is supposed to come on at 198 as i recall. The stock 192 degree thermostat means that at 170 it *is* going to run all of the time. The 220 on the high speed sounds right. I can check mine tomorrow if you need me to.

EDIT:
I'll be sure to check mine today. I'll post up this afternoon when i get home.
 

Don 95Vert

Founding Member
Oct 1, 1999
1,091
1
39
Delaware, OH
Oct 4, 2009
#5
  • Oct 4, 2009
  • #5
I'd flash it back to stock and reflash it - sounds maybe like the tune did not get loaded all the way or something got corrupted along the way. The fan runs during a flash all the time so that sends up a red flag to me. If that doesn't work, call SCT tech and see what they can do for you - maybe the canned tunefile got corrupted in the unit.

Dunno your year of car, but typically a 'new edge' PCM, this one is a GTG3 stock turns on high speed at 228*, low speed at 206* - this is pretty much around what a lot of them are set to. There are other factors that control it such as load and MPH. There is usually a startup delay as well. SCT's base files lower the HS to about 210* and the LS to 200*.

If you modded the fan temps via the handheld, I'd put them back to where they were originally you'll burn the fan up running it all the time.

Don
 
T

tonytaylor85

Member
Sep 3, 2009
126
0
17
Augusta GA
Oct 4, 2009
#6
  • Oct 4, 2009
  • #6
My car (2000 GT) defaults to 198 for the low and 206 for the high. I bumped mine down to 196 and it comes on when stuck in traffic about 2 degrees before it used to. 170 is the lowest option on the low speed fan which makes me think you accidentally selected it. Reflash with the above values and you should be fine.
 
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