A/C clutch not engaging

[ricko]

The A/C is not working in my 2003 Yukon, I've checked all fuses and relays and all is good, I jumpered the A/C relay to test the compressor clutch and it does come on when jumpered.

I replaced the low pressure cutoff switch and now the clutch egages like it should, it cycles on for a few
seconds then goes off, normal operation but still no cold air in the cabin.

I bought a set of manifold gauges today and did a static test, 45 psi on both high and low.

Running the engine with the a/c on max, gauges show just over 45 before clutch egages, when the clutch egages low pressure drops to 20, high pressure rises to 75.

But again, no cold air in cabin, the low pressure line coming out of the firewall is cold, but after the expansion tube it turns warm....is it possible that this tube is clogged???

Or any thing else I can try????

Any help on this would be appreciated.
thanks,
Rick

 

[bottomline2000]

is your rear air working?

 

[ricko]

YES...rear a/c does work.

 

[ricko]

Can anyone tell me what the specs are for low and high pressure, static and running???

thanks,
Rick

 

[Brender]

Blend Door Actuator?

 

[Brender]

I believe there are two of them.

 

[Brender]

One is behind the glove box.

 

[Brender]

Sorry. Trying to get to ten posts.

 

[SnowDrifter]

At a glance, 75/20 seems a bit low. Have you checked the charge in your system?