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K. Wiggins
K. Wiggins, ASE Certified Technician
Category: GMC
Satisfied Customers: 2992
Experience:  ASE Certified Technician, Associates Degree in Automotive Technology, 15+ years in the trade
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Act blows hot air. (We changed air filters) When I push the

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Act blows hot air. (We changed air filters) When I push the ac button it flashes and turns off and continues to blow hot air front/rear. At times will hear a hissing sound with just fan blowing, so we just don't run it. We are stationed overseas with limited resources, we have a good mechanic who without looking deep into vehicle it's the evaporator! My husband is back in the states and will get those parts. In reading up on it I've seen things about hvac case and some other lines. Is there other parts I should have him get prior to his return here?
JA: Where exactly do you think the noise is coming from? And how long has this been going on?
Customer: Hissing is front vents and about 4wks I guess
JA: What is the model/year of your GMC?
Customer: 2012 slt
JA: Are you fixing your vehicle yourself? What have you tried so far?
Customer: No we don't have proper tools. We replaced all the air filters we live in Africa so dirt is a huge issue
JA: Anything else you want the mechanic to know before I connect you?
Customer: We recharged it back in Dec prior to our deployment but not since we've been here

Hello, the flashing light indicates it is low/out of refrigerant. Hissing from vents is indicative of an evaporator leak.

I would get the evaporator, receiver/dryer, orifice tube, pag oil and refrigerant.

If your mechanic needs replacement info let me know.

Customer: replied 1 month ago.
Thank you very much!! I will have my husband get those and bring them back to Africa

You're welcome, it's my pleasure to help.

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