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kalamykid
kalamykid, Shop Owner/ Tech
Category: Chevy
Satisfied Customers: 4441
Experience:  I HAVE OWNED MY OWN SHOP FOR OVER THREE YEARS. I HAVE THE TOOLS AND SOFTWARE TO ANSWERE ALMOST ANY Q
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My compressor wont engage unless i jump the low switch. 2007

Customer Question

My compressor wont engage unless i jump the hi low switch
JA: What is the model/year of your Chevy?
Customer: 2007 chevy silverado classic 5.3
JA: Are you fixing your Silverado yourself? What have you tried so far?
Customer: Yes i replaced the thermo switch i replaced the hi low switch i replaced the relay
JA: How many miles are on the car? Has the car been starting normally?
Customer: 190000 an yes
JA: Anything else you want the mechanic to know before I connect you?
Customer: Not that i can think of
Submitted: 2 months ago.
Category: Chevy
Expert:  kalamykid replied 2 months ago.

Do you have a set of ac gauges so we can see the high and pow side pressures?

Customer: replied 2 months ago.
Expert:  kalamykid replied 2 months ago.

Connect the gauges up and tell me what the pressures are please with the engine not running.

Customer: replied 2 months ago.
106 low 101 high
Expert:  kalamykid replied 2 months ago.

Now start the engine and turn the ac on high and see if the numbers change please.

Customer: replied 2 months ago.
No an compressor not working
Customer: replied 2 months ago.
No change
Expert:  kalamykid replied 2 months ago.

Just to make sure there is no confusion, can you send me a pic of your ac gauges please?

Customer: replied 2 months ago.
How can I call you
Customer: replied 2 months ago.
I can't get the pic to u
Expert:  kalamykid replied 2 months ago.

Where did you get the new pressure switch?

Customer: replied 2 months ago.
Auto zone
Expert:  kalamykid replied 2 months ago.

Do you have an Orerily's near you? If you do can you go there and get a new switch and replace it please?

Customer: replied 2 months ago.
I got Two one from orileys an the other from Autozone
Customer: replied 2 months ago.
KNOW the low side is up to 115
Expert:  kalamykid replied 2 months ago.

If you can jump the plug for the pressure switch and the compressor will come on, then you have a bad sensor, or the shrader valve in the line is bad or stopped up and the sensor can not get a good reading on the pressure.

Customer: replied 2 months ago.
If I jump the switch it cools perfect
Customer: replied 2 months ago.
both my switches are bad
Expert:  kalamykid replied 2 months ago.

Then you need to replace the shrader valve in the line under the pressure switch. There may be bebris stopping up the shrader and not letting pressure activate the switch.

Expert:  kalamykid replied 2 months ago.

You will have to evacuate the system of freon before you can replace the shrader valve.

Customer: replied 2 months ago.
OK
Customer: replied 2 months ago.
OK I try that
Expert:  kalamykid replied 2 months ago.

Let me know when you get the shrader out. I would like to know if there is any debris on or around the shrader.

Customer: replied 2 months ago.
You me the one between the hi n low side right
Expert:  kalamykid replied 2 months ago.

The pressure switch screws onto the line, you have to remove the pressure switch and in the center of the part the switch screws onto, there is a shrader valve. you have to use a shrader tool to remove it.

Customer: replied 2 months ago.
I did not see a shared valve in it when I replaced it
Customer: replied 2 months ago.
OK I see it know
Expert:  kalamykid replied 2 months ago.

ok

Customer: replied 2 months ago.
Just wondering what are the gagees supposed too read
Customer: replied 2 months ago.
I can't remember how to do the math
Expert:  kalamykid replied 2 months ago.

Once you have the system working, the low side should be around 40 and the high side should be around 250 if it has the correcet amount of freon in it.

Expert:  kalamykid replied 2 months ago.

You do have a good static pressure at around 105.

Customer: replied 2 months ago.
I'm going to the store to pick up the puller most of my tools are still in LA at work
Customer: replied 2 months ago.
I'm back it's in
Customer: replied 2 months ago.
It felt a little gritty
Customer: replied 2 months ago.
OK I was a truck mec but wile at work a engine hoist broke an split my skull so had to relearn everything like a baby
Customer: replied 2 months ago.
I'm back
Expert:  kalamykid replied 2 months ago.

Did you get the shrader valve out?