How to program single fan

[patooyee]

I've read and mostly understand this thread:

http://www.hptuners.com/forum/showth...ighlight=fan**

But I still have some questions:

1. What does setting the number of fans do? No matter how many I put in, the tables stay the same.

2. ASSuming low speed fan = fan output 1 and high speed fan = fan output 2?

3. If I change the number of fans to 1 does the computer then ONLY control output 1? What does it do with state 2 in that case then?

4. How would I go about setting the system for one single-speed fan?

[patooyee]

Don't everyone rush forward at once now ...

[Shrek]

Start by posting your current tune, and a detailed description of how you have wired the single fan ... too many variables to discuss based on your initial vague post ... probably why you did not get any response.

Oh, and when you have your "hat in your hand", asking for help via the generosity of others, sarcasm tends to alienate rather than motivate.

[patooyee]

I'm sorry, my sarcasm wasn't meant to alienate. (Although it did motivate you to reply.) I guess I just have a dry sense of humor. I do feel like my questions were very specific and straight forward though, referring to specific settings within the OS which are fairly universal among all GM OS's, hence not needing my tune posted. Nevertheless, here it is.

buggy 6-20-13 misfire 1.25.hpt

It is all basically stock.

How I wire the fan is why I am asking the question. I'm guessing I will use the "low speed" fan (output 1 according to the OS?) to trip a relay that then powers the fan.

But then what is happening inside the OS with fan 2? Hence the above questions ...

[planethax]

With one fan you would have High and Low Speed, with 2 fans low speed would turn on #1 Fan and High speed turn on #2 Fan.
If I have read the system correctly.

[Shrek]

Fan settings are far from universal ... PCMs used different methods to control the A/C & E-Fans in conjunction. E38s also use different methods - Fan Control Module vs Fan Relays - each have there own unique setup.

Your tune is from an E40 - a two year only ECM anomaly. I never touch these - so I won't be of any help with the proper settings for this particular controller.

Now the readers know you are talking about an E40 - perhaps the right person will jump into this thread.

[patooyee]

With one fan you would have High and Low Speed, with 2 fans low speed would turn on #1 Fan and High speed turn on #2 Fan.
If I have read the system correctly.

So from the very basic electrical output POV, if I set a discreet fan system to number of fans = 1 then when fan output state transitions from 1 -> 2, fan output 1 turns off and fan output 2 turns on? And if number of fans = 2 then when fan output state transitions from 1 -> 2, fan output 1 stays on and fan output 2 also turns on?

You say if you have "read the system correctly." What do you mean by that exactly? Am I missing some sort of command line output?

Fan settings are far from universal ... PCMs used different methods to control the A/C & E-Fans in conjunction. E38s also use different methods - Fan Control Module vs Fan Relays - each have there own unique setup.

Your tune is from an E40 - a two year only ECM anomaly. I never touch these - so I won't be of any help with the proper settings for this particular controller.

Now the readers know you are talking about an E40 - perhaps the right person will jump into this thread.

You are referring to PWM vs. discreet fan systems. I am only referring to "one single-speed fan," which rules out PWM and refers to discreet only. I have looked up e38 and e40 tunes, they have the same discreet fan tables, both have the option to switch to PWM, which for the sake of this conversation, is not worth talking about. Both also came in factory applications that used both PWM and discreet. Thus, I think it is safe to assume that both use similar, or the same, logic control of the ECM outputs discreet vs. discreet, PWM vs. PWM. But even considering the remote possibility that they are totally different animals, that GM devised a completely different output control logic between ECM's, and that you seem to know more about e38's, perhaps you could confirm or deny planethax's theory of operation for an e38 only? And if what he is saying is not true in the case of an e38, how exactly DOES an e38 treat the fan output state transition from 1 -> 2 both when number of fans = 1 and number of fans = 2? I'm one of those guys who enjoys learning about a lot of things, even if they don't immediately apply directly to me ...

[patooyee]

Just in case, these are the tables I am referring to here:



Attachment 39907