Electric Fans cycling below max engine temp
04-04-2006, 02:31 PM
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Electric Fans cycling below max engine temp
I've got the nelson harness to control my electric fans via the pcm. I'm using EFILive and all the fan settings for the tune look correct, but the fans will cycle on and off at full speed when ever the truck is at 0mph. I've been told that the BCM may be causing the fans to come on and go off as some kind of safety measure. It's more of an aggrivation than anything for the fans to do this over and over all the time, but I would like to get it fixed. Anyone else have this problem/annoyance?
04-04-2006, 02:38 PM
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does eif live store their tunes in *.bin format (that can be opened with hp tuners)? if so email me your tune and I'll look at it, I have a 2003 also, same setup.
nickvrebel at gmail dot com
one other thing - is it the three relay or two relay harness? are both fans coming on or only one?
nickvrebel at gmail dot com
one other thing - is it the three relay or two relay harness? are both fans coming on or only one?
04-04-2006, 03:13 PM
#3
it sounds like it is running correctly.
when your truck reaches a designated temperature both fans will turn onto low speed until the temperature reaches a second turn off temperature
when your ac cycles one fan runs on high, and cycles with the compressor.
when your ac is on, and your engine reaches the preset "turn on" temperature both fans will run at full speed.
the cycling is normal, and proves that your fans are doing a good job of cooling by pulling enough air to reach the turn off value. it is annoying to hear those badboys kick into high but youll learn to ignore it after a while.
when your truck reaches a designated temperature both fans will turn onto low speed until the temperature reaches a second turn off temperature
when your ac cycles one fan runs on high, and cycles with the compressor.
when your ac is on, and your engine reaches the preset "turn on" temperature both fans will run at full speed.
the cycling is normal, and proves that your fans are doing a good job of cooling by pulling enough air to reach the turn off value. it is annoying to hear those badboys kick into high but youll learn to ignore it after a while.
04-04-2006, 08:18 PM
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Originally Posted by TXsilverado
it sounds like it is running correctly.
when your truck reaches a designated temperature both fans will turn onto low speed until the temperature reaches a second turn off temperature
when your ac cycles one fan runs on high, and cycles with the compressor.
when your ac is on, and your engine reaches the preset "turn on" temperature both fans will run at full speed.
the cycling is normal, and proves that your fans are doing a good job of cooling by pulling enough air to reach the turn off value. it is annoying to hear those badboys kick into high but youll learn to ignore it after a while.
when your truck reaches a designated temperature both fans will turn onto low speed until the temperature reaches a second turn off temperature
when your ac cycles one fan runs on high, and cycles with the compressor.
when your ac is on, and your engine reaches the preset "turn on" temperature both fans will run at full speed.
the cycling is normal, and proves that your fans are doing a good job of cooling by pulling enough air to reach the turn off value. it is annoying to hear those badboys kick into high but youll learn to ignore it after a while.
04-04-2006, 08:26 PM
#5
Originally Posted by mtnman
I think your missing my point here. The engine temp is below the values which I have the fans set to come on. The fans will come on at high speed for about 3-4sec then shut off when I'm sitting at a stop light. 3-4 seconds later, the fans will cycle at a high speed again, then shut off. This goes on and on while the vehicle is not moving. It has been happening since before I even used the A/C.
04-04-2006, 08:31 PM
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Originally Posted by Nickvrebel
does eif live store their tunes in *.bin format (that can be opened with hp tuners)? if so email me your tune and I'll look at it, I have a 2003 also, same setup.
nickvrebel at gmail dot com
one other thing - is it the three relay or two relay harness? are both fans coming on or only one?
nickvrebel at gmail dot com
one other thing - is it the three relay or two relay harness? are both fans coming on or only one?
04-04-2006, 08:40 PM
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got your email but I can't open that type of file with HP Tuners.
like KySilverado said, it's b/c of the a/c. with the 3 relay harness you should get one fan on at high speed with the a/c on and engine temp below the activation window. you will hear them good and strong turning on and off as the a/c compressor cycles.... you probably never noticed how much the a/c compressor cycles on and off before the fans, but belive me - it does it more than you realize it.
Try this:
start the truck, hood raised and a/c on - you should have only one fan on high speed. now as soon as it stops look at the a/c compressor clutch, I bet it stopped also (you may want to look at before and after with a flashlight if you aren't in broad daylight).
both fans should only be on high speed when the a/c compressor clutch is on and the truck is within the engine temp turn on parameters.
if only engine temp parameters are turning the fans on then both will be on at low speed.
Let me know if this explination helps any.
like KySilverado said, it's b/c of the a/c. with the 3 relay harness you should get one fan on at high speed with the a/c on and engine temp below the activation window. you will hear them good and strong turning on and off as the a/c compressor cycles.... you probably never noticed how much the a/c compressor cycles on and off before the fans, but belive me - it does it more than you realize it.
Try this:
start the truck, hood raised and a/c on - you should have only one fan on high speed. now as soon as it stops look at the a/c compressor clutch, I bet it stopped also (you may want to look at before and after with a flashlight if you aren't in broad daylight).
both fans should only be on high speed when the a/c compressor clutch is on and the truck is within the engine temp turn on parameters.
if only engine temp parameters are turning the fans on then both will be on at low speed.
Let me know if this explination helps any.
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04-05-2006, 12:42 PM
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Yep, must've been the climate control. This morning while the engine temp was below fan turnon temp, i turned the climate control off while in a drive through and the fans stopped cycling. I cant believe I didnt notice this before, DOH!
it lets me know its pulling alot of air though 
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