Hot Rod Air controlled by the computer?
04-12-2009, 02:54 AM
#21
Launching!
Thread Starter
iTrader: (5)
Join Date: Feb 2004
Location: Mobile, al
Posts: 294
Likes: 0
Received 0 Likes
on
0 Posts
Picked up the pressure sensor and fitting today along with the pressure sensor pigtail. Speartech must have removed the pressure sensor wires when they did my harness, because I have hooked my everything up and there are no connectors left. Since I dont have the pressure sensor provision in my harness anymore, what do I do?
04-12-2009, 08:44 AM
#22
Launching!
Join Date: Jul 2004
Location: Potomac, MD
Posts: 223
Likes: 0
Received 0 Likes
on
0 Posts
Ellis check the harness from the PCM connector end. I bet the connector was just cut off and the wires are still there. If not you will need to put them back. You can get the terminals or there maybe some unused wires you can move around.
04-15-2009, 12:51 AM
#23
Launching!
Thread Starter
iTrader: (5)
Join Date: Feb 2004
Location: Mobile, al
Posts: 294
Likes: 0
Received 0 Likes
on
0 Posts
I dont know if I will ever find those wires! I glanced tonight, but really didnt dig in. I may have to find some type of alternative. Im gonna give speartech a ring and see what kinda advice he has to throw in.
05-06-2009, 05:09 PM
#24
Teching In
Join Date: Mar 2007
Location: Texas
Posts: 32
Likes: 0
Received 0 Likes
on
0 Posts
hot rod air with ls1 can someone make a simple diagram to show how to connect a 2002 ls1 pcm to a regular hot rod air sanden compressor? it cant' be that hard...my hp tuner guy gave me 5 pcm wires and the HVAC v8 ls1 schematics. I don't think i'm gonna need 5 wires do I? how many wires will i actually need and what bank and number will they plug into? blue bank, red bank, number position?
05-09-2009, 01:02 PM
#27
TECH Resident
iTrader: (2)
Join Date: Jun 2006
Location: Roswell, GA
Posts: 802
Likes: 0
Received 0 Likes
on
0 Posts
No, what you described is a binary switch. The LS1 PCM uses a refrigrerant pressure sensor to read the exact high side pressure. The LS1 then in software acts like a trinary switch, cutting out the compressor if the high side is too high or too low, and turning on the cooling fans based on high side pressure.
05-09-2009, 04:08 PM
#28
Accumalator Two-Wire Pressure Switch Question... Rodder...streetcar540 raises a question I can't seem to recall the answer to... Should the binary two-wire pressure switch, thats on the accumalator/dryer, be used to interupt the computers "A/C Request" wire, that is activated by the dash control...OR...should it be used to interupt the A/C compressor power supply wire? (I'm talk'n a full computer control A/C set-up) Thanks
05-11-2009, 09:56 PM
#29
TECH Resident
iTrader: (2)
Join Date: Jun 2006
Location: Roswell, GA
Posts: 802
Likes: 0
Received 0 Likes
on
0 Posts
Rodder...streetcar540 raises a question I can't seem to recall the answer to... Should the binary two-wire pressure switch, thats on the accumalator/dryer, be used to interupt the computers "A/C Request" wire, that is activated by the dash control...OR...should it be used to interupt the A/C compressor power supply wire? (I'm talk'n a full computer control A/C set-up) Thanks
05-11-2009, 11:19 PM
#30
Launching!
Thread Starter
iTrader: (5)
Join Date: Feb 2004
Location: Mobile, al
Posts: 294
Likes: 0
Received 0 Likes
on
0 Posts
so im kinda stuck. Not real sure how to go about wiring mine up. I went to the junk yard and picked up the pressure sensor and fitting to braze in, but I dont have the pressure sensor plug in anymore. Speartech must have removed it. Im not gonna cut into my harness and find those wires either or take things apart to get to the pinouts. No big deal, i just need a plan B. I still have the one ecu green wire in the cockpit that speartech brought out and the 3 wire ac compressor plug in the engine compartment. Couldnt I somehow wire the 3wire plug and green wire from the ecu in with the hot rod air controls? That way it would at least kick off the compressor at the rpm I assign in hptuners as well as when the system is turned on to control idle.
05-12-2009, 02:34 PM
#31
If you are doing full PCM-controlled AC, you probably don't need the binary switch at all--the PCM will serve that function. If you want to keep the binary switch as a safety device because you don't completely trust the PCM, then put it between the A/C relay and the compressor clutch.
06-19-2009, 06:26 AM
#32
Launching!
Thread Starter
iTrader: (5)
Join Date: Feb 2004
Location: Mobile, al
Posts: 294
Likes: 0
Received 0 Likes
on
0 Posts
Just an update. I am running the AC without any tie-ins to the computer. Its running great. I still want to some how tie in a rpm relay that deactivates the ac. Really doesnt affect idle. Its definitely not seemless and you can feel when it kicks on and off, but its not bad at all. Im sure it is more efficient when the computer knows, but if you are like me and just want it running quick, then this is definitely one way to go. Ill work on this AC crap when there isnt record setting heat outside. Im still getting 22+ miles to the gallon with the setup in my sig and I have put 3800 miles on the car since may 2nd.
06-20-2009, 03:59 PM
#33
Launching!
iTrader: (1)
Join Date: Oct 2007
Location: Germany
Posts: 277
Likes: 0
Received 0 Likes
on
0 Posts
ok...what I'm hearing is that all I need is the three prong high pressure switch, not the 2prong low pressure switch?
If I'm wrong, then where does the blue low pressure wire go?
If I'm wrong, then where does the blue low pressure wire go?
