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First I will give the back history of how this whole thing started.

--Bought a cutlass ciera back in 2001 had it till it got stolen in 2010. These cars are beasts!!
--So I bought another from a lady out in the country.It belonged to her dad ex marine. Car really taken care of.
--Car was five bills. 92779 orginal miles. Interior good, exterior good, basically not much was in dreadful shape.
--lady did worst possible thing you can do to a car. Let it sit for three years.
--Then i buy it. Took three days to get it to turn over and run in park anyway.

--What needed replacing to resurrect it. Two injectors were not spraying, replaced. Plenum gasket, replaced. Alternator shot, replaced. Plug wire were dry rotted, replaced. Fuel pump not engaging, replaced. Fuel pump relay no good, replaced. EGR valve broken, replaced. Broken right exhaust manifold, replaced. Idle air control valve shot, replaced. Spark plugs were no bueno, replaced. Fuel pressure regulator would return two drops lol of fuel back to the tank, replaced. Schraeder valve on fuel rail leaked, replaced.

--what was checked or still good. Coils and Icm they sit on, Throtle body position sensor, Mass Air Flow, Oil pressure switch, Knock sensor, O2 sensor on right manifold, battery, Several relays in the relay rail at left bottom corner facing the car....

--ok now three days have passed car is running we drive it 25 miles or so to my home. I did all the work myself cleaned it up in and out somewhat took down all the wasp nests it had so I would not get stung anymore.

--This is everything that has happened previous to this point in time. The car is running pretty good. So now I am tackling the last issue it has. Oh wait for it wait for it yes did you say the ac does not work. NO. Well I will. The a/c does not work.

-- I need to know if the this 94 cutlass ciera v6 3.1 sfi has a hi and lo pressure cutt off switch/switches and where they are located. I have looked and I cannot find them. They are not mounted on the compressor. The only thing I have seen on the compressor is a relief valve in case you over fill it and the control valve inside of it which can be made out by looking at the back of the compressor. I know they can sometimes be located in a really inconspicuous location. Ok hope to hear back soon

Jdirk  

check on the high pressure line infront of the motor .. passenger side of the engine compartment where the small line connects to the condenser..   looks like item 22 on the link below...


warning....    as far as i recall.. there is NO valve core behind the pressure switch...   if you loosen it .. all the freon will leak out...


do you have a digital AC control system.????   where you push buttons to change the temp... like a caddy..


if you have an OFF and warmer button...   turn the key on.. and hold both off and warmer buttons in for about 6 seconds..  if all the dash lights come on...    look for one of the displays to flash trouble codes...

one last thing...    you might want to take a few minutes...

open the drivers door..    take out the bottom of the door opening panel..   roll back the carpet..   you will see a bunch of wires plugged into terminal blocks... take a good look.. make sure there are NO signs of burning... the cars grounds seem to be mostly connnected there.. and individual wires that are heavily loaded can burn...  

try this link.... for an idea where everything is...


94 cutlass ciera 3.1  ac parts diagram and list  

No. I don't have a digitally controlled ac system. The ac system in car is the kind where you just have levers and your either push them left or right or up and down. So no push or warmer buttons like the caddy's. Well the item 22 looks to me to be the ac cycling pressure switch. Also it's the only sensor of any type that I actually have found on the car or in the diagram you gave me through the link.  

Does that switch handle both high and low pressure situations? The reason I ask is because I thought that switch would cut off the compressor in a wide open throttle situation. What I'm not sure of is if that same switch would cutoff the compressor in a low pressure situation so the compressor doesn't fry. And in that assumption there would not be a hi and lo pressure switches but one switch to do the job of both. I will state my assumption this way because I'm understanding other ac systems have two individual switches.( hi pressure and lo pressure switches )

Thanks for the link and info so far.


Jdirk  

did you notice the description of it below the image....

its NOT  a switch... its a pressure sensor...

systems with pressure sensors are usually PCM or ECM controlled ac... at least the compressor is controlled by the PCM/ECM....  

Right like I said its the only sensor I've found on the car or in the diagram you provided. I realize its a sensor. Calling it a switch was not appropriate I guess. I also had a petty good idea the pcm/ecm operates or controls it. So is that the only one? I see no hi or lo sensor s or switches. Also, you made no reference or  explanation if indeed the ac pressure sensor operates under the assumption I stated.  

i have been distracted.. and was just running out the door as i posted...

autozone.com has a free repair info site.. but has limited about of ac info...

for additional info...  you are probably going to need to access...    alldatadiy.com      or   eautorepair.net   both of them have the full repair info online...   they just are not free.. but they are not a lot of bucks..

i only have limited amounts of climate control books and info...   and most of the info is NOT well covered in the drivability books i have..

how about a wiring diagram...  



you will notice that the dark green and white wire that controls the ac clutch relay looks like it connects to the dark green wire.. but if you read carefully.. both of those wires go to the ECM/pcm for computer control.....



you will notice in this image.. which is for the 95/96 models with a 3.1.. that the dark green and white wire comes from pin C2 on the bottom side of the diagram...


some 94 and most 95 models were OBD1.5...  which makes using an inexpensive scan tool out of the question...

depending on where you live.. you might check your local CL  for tools    look for  OTC  or scan, or scanner...

obd 1.5 uses the later connector but has the earlier data stream...   are the ends of your data link under the dash board straight on the ends...  |________|    or angled...\_________/   which would be OBD1.5...  

the wiring diagrams above are LARGER than you can see on this format...   open in a new window or print them... printing is better..

if you have tapered ends to the connector under the dash..   a harbor freight tools   98164 might be able to access the codes.. but might not show data.. i have not had one in... and i have not just a 98614.. but i have an actron 9110 scan tool... and a OTC extended monitor i got off CL with a lot of cables...


you might also want to go back to the link i posted with the diagram.. look around at the other diagrams around.. so you might be able to figure out where the ac clutch relay is, if you don't know already...  

Thank you for the diagrams I'll try to use them as best as I can and I'll try to understand them as best as I can. Ill assume the system has that one sensor. Let me ask something different. I believe I have found the clutch relay. Its on a rail bottom left facing the vehicle. There s the clutch relay and one for the blower motor which works. The other three are for the radiator fan the primary and secondary I'm assuming for a high and low speed. And the fuel pump relay for a total of five relays. Well the relay for the clutch is getting power from two red wires one green w/white stripe goes to pcm/ecm the solid green wire goes to clutch magnetic coil plug paired in with a ground.

The problem is the relay is getting power but the wire going to pcm ecm has low voltage. Checked it with test light. The wire going to clutch magnetic coil has no power at all. There is a fuseable link between the clutch relay and the plug connecting to the clutch. It does not seem bad. Its kind of stiff is all. Anyway there is a set of three inline fuses under the passenger dash two have power one does not key/car on or off. I know one is for the door locks but the other two I have no clue. What are these for? I have a hunch that might be related to the clutch relay not producing power to the wire going to the clutch magnetic coil plug.

Jdirk  

when testing the relays...  the pink wire has switched voltage on it..

the red wire should have constant voltage...

try to NOT probe the wires to the ECM...    the pink wire on the upper left corner of the upper diagram supplies power to the coils of the relays...   except for the clutch relay..   where it seems to supply power also..


try not to probe with a test light the wires to the BCM...    if your test light has too much current draw do to a bulb that takes over ONE amp to turn on.. you have a good chance of blowing out the chip in the computer that pulls that circuit to ground..

the coils take less than ONE amp to operate each...

if you notice the time..   my main computer crashed..   power supply problems.. i was working on a stack of dead mac laptops to get one up and running..  i guess you can tell i was success full for one..

testing farther is going to require a scan tool to force the relays into test mode.. where the relays are all activated..

or you can verify that the system is working and supplying power by taking the guts of the relay out.. plugging it back in.. and manually closing the contacts..   for a trial...

on earlier models of that car..   there was a wiring problem with the orange power circuit to the AC system..   where the fusible link on top of the starter would burn..    taking out the AC and defroster fan..    again this was on earlier models with the 3.1 and 2.8 ...  the short turned out to be above the gas pedal where the wiring loom rides over the top of a stamped steel guide..     the edge is sharp and it cut through the harness..   since the wiring harness is mostly made the exact same way each time..   the effected wires were cut and shorted to ground many times..    i needed parts for one that was only partially burned..    out of 7 or 8 cars of that exact model..    there was only one that was not burned..

so... if you DON'T have power on the orange wire....   or you don't have switched power on the pink wire..  and you trace it back to the fusible link..   time to start looking..    the effected models had the AC control relays mounted in a panel below the glove compartment..

please verify that the radiator cooling fans properly cycle on and off then back on and off before sending the car out of the driveway...   i don't want you to over heat the engine..