A/C Signal Wire

[rosscob]

There is someone on LS1 tech that is talking like they have it all figured out, but don't have any confirmed results yet.

He is trying to mimic the '05 programming and activate pin #33 that is dead on the older PCM's. Some thing tells me it's not gonna work.

So far GMCwantsLS1 has the best solution I've heard, but it I don't think it's been tested either.

[TXsilverado]

any updates? i cant seem to find the thread over at tech either...

[rosscob]

Here is the thread from Tech. In the beginning it showed promise, but died fast.

http://ls1tech.com/forums/printthread.php?t=330567

[TXsilverado]

im no electrician, so dont slap me if this is ignorant what would happen if you pulled the ac controls out of your dash and just tapped into the ground from it?

then when its turned on it will stay on until you turn it off...or am i missing something?

[rosscob]

Originally posted by TXsilverado@Jun 15 2005, 12:35 PM
im no electrician, so dont slap me if this is ignorant what would happen if you pulled the ac controls out of your dash and just tapped into the ground from it?

then when its turned on it will stay on until you turn it off...or am i missing something?

I don't think you are totally missing the point. I think the A/C controls put out a postive charge on the A/C request.

Jeff's idea on the A/C pressure switch is still the best i've heard, assuming the guys at tech can't figure out how to make the PCM control the second fan.

[SlammaDingdong]

Originally posted by rosscob+Jun 15 2005, 02:02 PM--><div class='quotetop'>QUOTE(rosscob &#064; Jun 15 2005, 02:02 PM)</div>

<!--QuoteBegin-TXsilverado

@Jun 15 2005, 12:35 PM
im no electrician, so dont slap me if this is ignorant what would happen if you pulled the ac controls out of your dash and just tapped into the ground from it?

then when its turned on it will stay on until you turn it off...or am i missing something?

I don&#39;t think you are totally missing the point. I think the A/C controls put out a postive charge on the A/C request.

Jeff&#39;s idea on the A/C pressure switch is still the best i&#39;ve heard, assuming the guys at tech can&#39;t figure out how to make the PCM control the second fan.[/b]

I&#39;d really like to figure this out and be able to do it w/o tearing stuff up.

Tapping the dash A/C would work either way (+ or - initiation), since a relay could be used to provide proper polarity to the harness relay (+ side in this case). Just not sure how easy access to the dash controls is.

Where&#39;s the A/C accumulator located? In the cab, passenger side? Is the low pressue switch fairly accessible?

[GMCwantsLS1]

The A/C accumulator is located on the firewall passenger side of the engine compartment. It is the aluminum tank you will see with the AC hose coming from it. The low pressure switch is screwed on to a fiting on the side of the accumulator and has two wires on it. One should be hot when you turn on the A/C on the dash, the other is controled by the pressure it sees and sends a signal to the PCM.

[SlammaDingdong]

Originally posted by GMCwantsLS1@Jun 19 2005, 06:27 PM
The A/C accumulator is located on the firewall passenger side of the engine compartment. It is the aluminum tank you will see with the AC hose coming from it. The low pressure switch is screwed on to a fiting on the side of the accumulator and has two wires on it. One should be hot when you turn on the A/C on the dash, the other is controled by the pressure it sees and sends a signal to the PCM.

No problem, I see that. There&#39;s a WeatherPak connector, w/ two wires, that hooks up to the switch. One of the those is a PCM signal and the other will go hot w/ AC on? And it&#39;s a positive (+) switch source, just like when using the wire to the A/C compressor clutch? That should be pretty easy.

Okay, I&#39;m going to try this.

Thanks GMCwantsLS1.

Jeff

[SierraCrew]

I was thinking about doing something similar to this, but a bit different. I have been trying to sell the FAL&#39;s but if not, I&#39;ll try this. How could I run the fans on an adjustable temp controller like that taps into the radiator and then just have a switch to turn run the fans full speed with the anytime I have the a/c on. I very rarely run the a/c thats why and I really dislike having them connected to the a/c clutch wire.