91 Ford Explorer A/C issues

[nitris]

with the car running and a/c on i only get 14.6 volts here circled in black

 

[shucker1]

Were you able to get to the wiring diagram link.

1995 Model year is a close as it will get. From what I saw last night the relay only becomes "Active" at WOT and it drops the compressor offline.

If you look at it you should be able to solve your problem. To me it seems like you have a wire completely missing.

You are going to need a power feed, a load side (being the compressor) and at least 2 more to drive the coil when needed.

 

[nitris]

Yea seems as if I'm missing a wire as well... I did get the diagram... do anyone have pics to verify a missing wire?

 

[shucker1]

If you get a long enough jumper wire you can jump from the pressure switch directly to the compressor clutch coil to see if it locks in.

Do a point to point check from your relay back to your pressure switch and then from your relay back to your A\C clutch coil connector. That will tell you which one is missing.

Check around the area of the relay socket to see if you have any stray wires hanging around \ burned off with nothing connected. My bet is that one of those is your victim.

Also if you pay close attention to the relay itself there are 2 small blades and 3 big blades. Chances are would be that the small blades are the coil and the big blades are the relay contacts themselves.

 

[nitris]

If you get a long enough jumper wire you can jump from the pressure switch directly to the compressor clutch coil to see if it locks in.

Do a point to point check from your relay back to your pressure switch and then from your relay back to your A\C clutch coil connector. That will tell you which one is missing.

Check around the area of the relay socket to see if you have any stray wires hanging around \ burned off with nothing connected. My bet is that one of those is your victim.

Also if you pay close attention to the relay itself there are 2 small blades and 3 big blades. Chances are would be that the small blades are the coil and the big blades are the relay contacts themselves.

thx, i've been hunting down stray wire and found nothing yet:thumbdwn:, im trying to match wire color using the 94' explorer diagram to see whats missing... unfortunately since I just bought this truck I have no idea what was working or not... the old owner stated it needed freon which was not the case, it had to have been working though because the old compressor was damaged with metal shards from the high pressure hose all the way to the orifice tube... I'll keep hunting but this is becoming a huge mystery.

 

[shucker1]

Don't give up.

Your almost there.

 

[nitris]

still no luck,
I think there is a problem between the pressure switch and the control console for the HVAC... The purple line per the circuit diagram goes directly from the pressure switch to the HVAC control assembly... so i pull the dash only to find 3 purple cables, of which two are on the same socket and same port (bigger)... the other is on a separate socket(smaller) none of which toned back to the pressure switch...and since the diagram don't state what's what i'm left scratching my head... I did see a second relay on the diagram but not sure if its specific to my 91' or the 94'... i did however find that when pressing the a/c button the purple cable on the smaller socket got 12 volts and lost it after it was depressed... maybe this is the line that should go direct to the pressure switch.... where is the low pressure cutout switch or do we even have one on the 91' truck... it could be that as well but right now i'm too tired to test tonight so I shall try again in the AM

 

[nitris]

UPDATE ok after a good night's rest.... i flushed my coolant system to clear my mind and come at the problem with fresh eyes.... As I was looking at the wire at the accumulator I think I came across the mysterious low pressure cut out switch... it was actually damaged and barely holding the two connectors together with white tape... I also noticed that the the wiring to this switch connected directly to the pressure switch on the accumulator, directly to the WOT relay and directly to the compressor... this maybe the mystery of why the purple wire from the A/C button in the cabin had power but when i traced it back to the pressure switch I got no tone or voltage... autozone seem to not have it on its website as its a 4 wire connector and not 2wire as displayed online.

in the pics is what I assume is the low pressure cut out switch... can anyone confirm this, as I think this maybe the problem I have been searching for (for future users if pics are ever removed the low pressure cut out switch is in front of the accumulator connected in the same harness as the pressure switch, WOT relay, and compressor connector 91'ford mine was orange)

 

[nitris]

anybody know where I can find this part and is it called the low pressure cut out switch? i've tried autozone, pepboys etc with no luck unless I'm looking under the wrong name.

thanks

 

[nitris]

UPDATE FIXED So I finally got that connector fixed and the A/C is finally working... I literally have a brand new system in this truck now aside from the condenser. I couldn't find the part anywhere, so instead I used a good ole high temp zip tie

.... it held it together just as good as a clip would have....

not like that tape the previous owner put on it. The only question I have left is my suva levels.... I know this truck takes 28oz empty... and I have put in 2 cans with a slight bit of spillage... what should my gauges read if i try to add the extra 4oz to top off the system im reading about 25psi on low and 225psi on the high at end at 70 degrees outside sitting idle

I couldnt help but to laugh at the RETARD indication on the low pressure gauge if someone ever gave it that much suva.... I'm just noticing this lol

 

[shucker1]

What were your test conditions when you took the pictures of the gauge readings?

I always do mine with the system on max A\C, Blower on High and truck windows open.

I put a stick thermometer in one of the vents.

Perhaps a small squirt more would bring the low side up a little bit.

In the picture your low side pressure switch is about to trip and do it's job to let the low side pressure come up and keep from damaging the compressor.

 

[shucker1]

P.S. Good job on the fix.

Congratulations and enjoy your new A\C!

 

[nitris]

P.S. Good job on the fix.

Congratulations and enjoy your new A\C!

Thanks... I'll add a tad just to top it off... I had the A/C on max cool with the windows down and the front doors wide open... I'm just glad to get past this repair... now on to replacing bushings and chasing down this power steering slow leak..

 

[nitris]

P.S. Good job on the fix.

Congratulations and enjoy your new A\C!

Thanks... I'll add a tad just to top it off... I had the A/C on max cool with the windows down and the front doors wide open... I'm just glad to get past this repair... now on to replacing bushings and chasing down this power steering slow leak..