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Q: AC blows hot in the front, cold in the rear

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I had leaking condenser and compressor's O-rings and shredder's valves that I have replaced. I vacuumed the system for 2 hours and performed vacuum test for 30 min. Low side reading was between 28-30 and high side arrow never moved towards the zero - no leak. I have filled system with refrigerant (I noticed when I was done with third can 340gr each, I had some sign of cold air and when I filled with correct amount no cold air at all) and front is hot and rear is cold - really cold. I am in Vegas so it is hot. I was very confused as when the system was leaking all I had to do was add more refrigerant and I would have cold air for a few days but when I replaced everything to restore vacuum ac is not properly working. I had pulled error codes that there was no communication between ECC and DDM (I have 5 dumper motor modules) I erased the codes and performed identification of each DMM (via VIDA using DICE tool) and then recalibrated ( by the way all DDMs responded to all the buttons before

My car has 139000 miles.
My car has an automatic transmission.

Hello. It sounds like the blend door actuator is failing. This door is responsible for blocking off air flow to the heater core when the air conditioning is on. I would recommend having the blend door actuator tested using the manufacturer’s recommended procedure by a qualified professional to determine if it is functioning properly and the rest of the AC inspected in order to pinpoint the underlying problem. If the blend door actuator fails this test, I would recommend having it replaced in order to resolve this issue.

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