A/C Disable Settings

[glennhl]

I have a 2006 Corvette LS2. I just got HPTuners and I've downloaded my stock BIN. After studying it I've noticed that the A/C disable under System and A/C the disable RPM is 7083 rpm and the disable TPS is 200%. That sounds like the A/C never turns off at WOT like it should. What am I missing?

[5_Liter_Eater]

As we've been talking about on corvetteforum:

You're right, these stock settings will never disable the A/C.

I tried setting my disable RPM to 4000, re-enable to 3000 and set my disable TPS to 75% and re-enable to 50%. Then I went for a drive logging the AC clutch and AC disable (WOT RPM) and what I found was that the AC clutch did not respond to these settings, the clutch would cycle regularly like it should but did not disengage when one or both of the above parameters were met. The AC disable status bit never changed from No.

What is the deal?!?

[Chris@HPTuners]

The RPM must be below the RPM for the clutch to disengage (it works the opposite to the way you think it should). The TPS must exceed the limit.

Chris...

[8850]

The RPM must be below the RPM for the clutch to disengage (it works the opposite to the way you think it should). The TPS must exceed the limit.

Chris...

Can you post some numbers or a table to show us what you mean? I want my AC compressor off when I reach about 4000 rpm or 90% or so throttle. Thanks...

[Chris@HPTuners]

Can you post some numbers or a table to show us what you mean? I want my AC compressor off when I reach about 4000 rpm or 90% or so throttle. Thanks...

set the RPM values to something higher than 4000 rpm, then set the TPS values to 90%.

[8850]

set the RPM values to something higher than 4000 rpm, then set the TPS values to 90%.

Gave that a try but status bit still indicates the compressor is on. It won't turn off with 4294 disable, 3950 enable, same as my 98 Camaro, or even with 2000 rpm disable in the program. Only way to get it to say off in the status bit is to punch the ac snowflake button on the ac controls. What am I doing wrong?

[5_Liter_Eater]

The RPM must be below the RPM for the clutch to disengage (it works the opposite to the way you think it should). The TPS must exceed the limit.

Chris...

So you mean the Re-enable should be higher than the disable RPM?

[8850]

So you mean the Re-enable should be higher than the disable RPM?

I tried 1500 rpm in disable and 2500 in re-enable. The status bit indicates the compressor is still on. I had 90% throttle disable and 50% re-enable. I just don't think these commands are working.

[5_Liter_Eater]

I just don't think these commands are working.

I would have to agree.

[glennhl]

Someone over on Corvetteforum says that the service manual states that the A/C turns off at WOT. Is it possible that the BCM is doing this instead of the PCM?

[8850]

I sure hope that's the case Glenn. Seems to me were the compressor engaged at 6500 rpm would be taking a tole.

Curious why we have the commands in HP Tuner if they do nothing?

[5_Liter_Eater]

I would think that at least the aC compressor status bit would still function regardless of what it was being controlled by. Maybe not the AC RPM disable bit. Just my guess.

[TrekGTO]

If TPS has a max of 88% y would you set disable to 90%

[5_Liter_Eater]

Doesn't matter really. Set it to whatever you want, it dont work.

[BennyHHR]

Same problem here with a 2.4 LE5 E67. Doesn't matter what the settings are, the results have absolutely no correlation to the status. Seems to be a common problem with these newer ECMs.

[Bill@HPTuners]

There might be a couple of parameters not yet added from the logs Joe has supplied us with maybe a min gear or min mph or something for the enable & I think theres a disable timer as well that will keep it disabled for a set amount of time after its been initially disabled.

[TrekGTO]

I wonder if HPT is fixing this OR just working on Ford? Still seems like would be a setting less than 88% if TPS max is 88%

[8850]

I wonder if HPT is fixing this OR just working on Ford? Still seems like would be a setting less than 88% if TPS max is 88%

Log ETC Position and you will see 100%.

[Bill@HPTuners]

I wonder if HPT is fixing this OR just working on Ford? Still seems like would be a setting less than 88% if TPS max is 88%

Theres really nothing to "fix", if anything maybe something we can "add" adding things to 50 or 100 different calibrations isn't something that can be accomplished in a half hour. But as far as the calibrations go theres nothing broken in the calibration as what is there by gm is there. As for the 88% thing, its covered pretty well in the sticky at the top of this forum.

[5_Liter_Eater]

The ETC/TPS discrepancy is moot. The problem that this thread is about is that any combination of maxing out and/or minimizing the AC disable RPM and TPS values does not result in the AC cutting out. Whether this is a bug in the GM OS or a bug in HPT I have no idea but this is another gen 4 table displayed in the GUI as being editable and has no effect on the operation (the other one off the top of my head being switchpoints).