OttawaMark

iTrader: (3)

Is the 0-5v reference wire that talkes to the PCM?

Thanks

OttawaMark

iTrader: (3)

17 GY 2700 A/C Pressure Sensor 5-Volt Reference

Service Information

OttawaMark

iTrader: (3)

Nope, wrongo. That schematic is for an 2005 Cobalt...disregard if you have a later model as pin 17 is empty. Wrong one anyways, it is pin 26 on a 2005:

26 OG/BK 380 A/C Refrigerant Pressure Sensor Signal


Now which one is it on my 2007?

ChineseWop

I dont know what pin number it is but on my 06 on the blue plug that goes to the pcm (the top one) its the red/black wire. Should be the only one in the harness.

5hizn1t

Here's the info on the 2007 Cobalt A/C Refrigerant Pressure Sensor
LE5/LSJ engine:

Pin Wire Color Circuit No. Function

1 BK/WH 2751 Ground
2 GY 2700 5-Volt Reference - 1
3 OG/BK 380 A/C Refrigerant Pressure Sensor Signal

L61 engine:

Pin Wire Color Circuit No. Function

1 BK 6256 Pressure Sensor Low Reference
2 GY 6255 5-Volt Reference - 1
3 RD/BK 380 A/C Refrigerant Pressure Sensor Signal

Below is the schematics of the A/C system. Sorry, it's a bit blurry. If needed, I can get a bigger, clearer pic of it.

OttawaMark

iTrader: (3)

Well done 5hizn1t, that wins the thread.

paddock

iTrader: (2)

OK.. I"m curious.. what was the point of this exercise??

OttawaMark

iTrader: (3)

The point being was to use the 0-5v reference from the AC pressure sensor as a tap to log wide band through the basic version of hp tuners.

paddock

iTrader: (2)

Is that the wire that I need to put a toggle switch on??? I've been trying to figure that one out for a couple weeks now!!!!

PM me details please!!??

OttawaMark

iTrader: (3)

Yes, that is exactly it.

Crawl underneath, cut the orange/black wire coming from the refrigerant pressure sensor (small hands help) and splice two longer lengths on each cut end. Run those longer lengths to where you want your switch to be.

Get a 2input/1output switch, mine was actually 120v rated but works just fine.

Connect orange/black going to PCM to output on the switch.

Connect orange/black from AC sensor to one of the inputs.

Connect WB 0-5v output to the other input on the switch.

Voila, AC or WB logging but not both

paddock

iTrader: (2)

so any three way toggle will work??

OttawaMark

iTrader: (3)

Yep, mine was actually 120-240v rated but flows low volts through it with no degredation.

paddock

iTrader: (2)

I'm guessing it's just a signal wire set up, so voltage might not be as much an issue..

Dude.. I can't thank you enough!!! My tuner guy has been so busy that he hasn't had a chance to get me the info for that switch set up. Many thanks!

YelCal7

iTrader: (1)

Sorry to bring this thread back up. I have 3 way toggle switch, if I hook my Wideband on toggle switch where I hook up ground wire from Wideband to where ?

OttawaMark

iTrader: (3)

Iirc, my WB ground wire is terminated to a bolt on the passenger side interior fuse panel.

YelCal7

iTrader: (1)

I did that and it's a no go. Could it be blown fuse for A/C ? Or A/C turn off in my PCM ?

YelCal7

iTrader: (1)

I have an 06 and I did checked my wires from A/C pressure sensor. It's Red/Black and I did what you did but for some reason it's not turning on. I use 1 wire from A/C sensor plugged to the top of the Rocker Switch, 1 wire go back to PCM go back to PCM go to the bottom of rocker switch, 1 from Wideband go to the middle of rocker switch, then last ground wire from Wideband hook on the metal. My Wideband still not turned on, it's AEM UEGO Wideband.

OttawaMark

iTrader: (3)

When you say still not turned on, do you mean as in no power whatsoever?

Where are you getting your 12v power from?

The AC sensor wire you need to tap is but a 0-5v reference, resisted from a constant 5v power that you dont lol...I know this because I tapped the 5v constant first and couldn't figure out why my gauge read just fine but in HPTuners it was full lean. Anyways, tapping it all properly is moot if you don't have a 12v supply.

I tapped my IC pump power for the 12v, which itself was running off a spare fuse in the engine bay fuse box.

YelCal7

iTrader: (1)

I use 12v from power outlet but can't figure how I hook that up to.

OttawaMark

iTrader: (3)

Which power outlet?

And does the gauge light up? Or is it dark?

YelCal7

iTrader: (1)

I had tried to do rocker switch with 5 pin relay, I can't get it work right. I attach Wideband ground wire to 12v ground wire n 1 go to 5 pin relay. It won't work, I took off from 5 pin relay and hook on rocker switch then it turn on. I did 5 pin relay hook on to rocker switch and I can hear click when I turn on rocker switch. It's a PAIN IN THE ASS! I am trying to figure out how ? Do I need to have ground wire from A/C pressure sensor ? I need to have wire diagrams to show me how to do this and get it working.

YelCal7

iTrader: (1)

I did top power outlet. I custom made rocker switch to go there.

OttawaMark

iTrader: (3)

YelCal7

iTrader: (1)

This is GREAT! I will do that today! Alittle confused with Rocker Switch, White go to the Top, PCM go to the Middle, A/C pressure sensor go to the bottom. Right ? Just double check!

YelCal7

iTrader: (1)

Your show Orange/Black but I checked mine is Red/Black from A/C pressure sensor. Mine is 06.