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Discussion Starter #1
No cold air. I have no reference voltage at air compressor blue wire. I do have 12 volts at green wire . Looking for a good wiring diagram or a knowledgeable person that could help with this issue . Please pm me or text 305-951-2715. 2009.5 G8 GT .
 

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The service manual says that the green wire "should" read 12 volts to a good ground source, so your good there. You should find near zero resistance on the blue wire to a good ground source with the ignition turned off. Both of those wires (the green with power an the blue reading ground potential) both come from the HVAC control module located near the right side kick panel. If that control valve is bad, "Thawk" has a thread for the fix. For sure, you know your system refrigerant quantity is correct ?.
 

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Discussion Starter #3
I do not know the amount of Freon in the system. I will take the car to a Airconditioner tech so they can add the proper amount . Do you know what pins the blue wire and the green wire are at the havoc ? And I will check resistance at blue wire. Thank you for the info !
 

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The Green wire goes from pin #2 at the compressor solenoid, to pin #7 of the X1 connector on the HVAC control module. The Blue wire goes from pin #1 at the compressor solenoid, to pin #6 of the X1 connector on the HVAC control module. Unless you "can not" find a ground reading at pin #1 of the solenoid connector, I can't see the reason to try to get to that HVAC module at this time.
 

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The dark blue wire is a ground from hvac module,the green is a pulse width from hvac mod.the green should be full voltage until module backs it off some as it reaches cooling set temp.before you go crazy, remove a/c belt aside and make sure the 7mm bolt in middle of comp pulley is not seized and is spinning with comp pulley first, the comp shaft and pulley are linked with a pin inside if comp starts to lock up the pin will break disengaging the pulley and comp shaft
 

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Discussion Starter #6
So your saying I should have a ground at the blue wire at all times ? I do have 12 v at the green wire all the time . But nothing at green . I did get a good ground and pined it in the blue side of conector and compressor comes on sometimes. If it does not come on I rev the engine to 4,500 rpm and it usually come on .
 

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best way is to probe both comp. wires into volt meter, start car, turn on a/c, should show 12 -15 volts until hvac module pulls on time of green wire to 4volts
 

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Discussion Starter #8
Ok. Will do that next. With green wire but I am supposed to have a ground at blue wire correct?
 

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do it with both wires straight into voltmeter.start it turn on a/c and let me know the voltage,yes the green is ground from havac module, but in a rediculously tight area do both to the voltmeter,and we will go from there
 

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you have to use both wires into voltmeter not separate, both blue and green to voltmeter at same time,please tell me it is not a V6
 
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