AC Quit

[Bigfish95971]

Sorry about that I do not know what the pressure was. Thank you for responses so far.
Let me update with the same post I put on my other forum. Not no response, just not one that helped with right answer yet. Did everything suggested but had to to take to shop for some. Thought I would have seen more with same exact issue and their answer. Not yet.

Questions?
Can Fluid be vacuumed out and refilled at a shop without the clutch/ compressor working?
Gave up and took it to a shop and had it Checked and "diagnosed". $175 later, They said they evacuated it and refilled it and put in 2 new Schroeder valves(valve cores i guess) for 20 dollars each,(one blew out and they had to do it again)They said it had a code for "no communication between the PCM and AC control unit"? Did not catch number. They said it needed new heater control unit. I replaced with matching used one and did reset. Still no love. Put old one back in.

Jumped low side sensor so far has not helped. Had 4.8v to it. Does it go directly to the clutch through the relay or through the PCM or something else?

Next I am going to jump the clutch coil while running. I did it before not running.

What is next? New PCM? Is used Chevy one plug and play? Does anybody around Yuba City, CA, have a sophisticated Scan tool that that can help me?
Does anybody know a Chevy truck(rather than Tahoe) forum that gets more attention than the one suggested above?
Other thoughts?

 

[Bigfish95971]

OK I have narrowed it down to two things, I need a new plug to the harness wire to the solenoid because I broke off the ground on it. Got that here now.

Now the real problem all along, the system seems to be working correctly but the solid green wire from the PDC relay to the clutch solenoid is not getting power from the relay. The relay is working and closing to send power,(and when jumped) but it appears to be open(bad connection to the green wire.

The question is how do I connect it or replace it? I have removed the cover and turned over the PDC to the bottom, I have found the wires, I believe, but how do I get to the connections to fix or get power for anew wire?

I pulled the bolt loose on that center black block and it would only come part way off, decided not to force it any further?

What next, help or video?
Its going to be 105 to 115 the next few days.

 

[Bigfish95971]

Further the green wire works, the relay is not grounded and wont close.

More info,

• a moment ago
• 
  
  GROUNDS!
  
  What do you know about grounds on a Chevy and on the relays in all fuse boxes?
  
  I have juice to the always hot post of the relay.
  When the car and AC are turned on and running(no cold) there is power to the input trigger wire.
  Can not get the (or replacement) relay to trip.
  I have the PDC flipped up bottom up.There is a pair of black and white wires on a hole between the two hot wires, solid green and green /white. I think it is ground from the low pressure sensor/switch which I think is working. It does not trip the relay even if I ground those black/white wires to direct ground.
  
  Any Chevy experience, Ideas?
  Thanks.

 

[Bigfish95971]

Anybody still with me? Down now to replacing the clutch now, coil has been shorted out. Anybody changed one in the truck, I have access to the tools on rental. Any tricks to access and replacement with the compressor in place?

 

[nonickatall]

YouTube is your friend...

 

[Bigfish95971]

Thanks, it must be morning over there. You know any Dodge guys over there from Dodge forum?

 

[nonickatall]

It wass 11:00 am so after third coffee.
How do you come on Dodge?

 

[Bigfish95971]

I have a 99 that I post on hours daily in 2nd gen sections helping people daily. There is a gentleman now in Germany goes by Ukraineram on the Dodge Cummins Diesel Forum site that. He moved to Germany after the war started. He is building a badass 3500 somewhere in Germany where his company moved him.

 

[Bigfish95971]

Is the front end shrouds and so on the same on an 03, that looks older?

 

[TollKeeper]

A little late to the party, so.. Mine is for a 1995, so a different system. But I found it relatable to your condition.

I had the same issue on a 95 Silverado. The catch was that if I turned on the defrost, it worked (as it should be default), but not in any other mode.

By default, if the system meets the requirements in the various sensors, defrost will always turn on the AC unless the ambient air temp is 18* or lower (if memory serves).

Mine was the actual switch inside the dash controller head unit. It would light up that the AC was on, but it never actually made the physical connection to turn on the AC compressor.

I replaced my dash controller head unit, and it worked perfectly from then on out.

On your 2003, there are different modules involved, from the dash head unit, to the climate control module, ambient outside temp, interior ambient temp, driver ambient temp, and who knows what else.