Dodge intrepid 1995 air conditioning system?

i have a 1995 Dodge intrepid 3.5 L with a ATC control Digital AC module and a 12 Volt relay on the dash module. It's a 12 volt relay with 4 prongs not 5 and is said to be the rear windowo defroster relay. The part is not longer made in the US per dodge and Chrysler dealers here. Whole Module is 525.00 but has no relay in the rear if pluged in. Told to go to the Junk Yard to get. Compressor is fine. Self diagnotics read 23 ATC Blend blend door feed back control ? and and ATC head communications failure. Works some time then goes from dash fan to deforest fan . The some times works fine. . The 12 volt relay which module is a chrysler product , pulls only 10.5 on a volt meter. . Could this be the problem , low voltage. . Compressor is fine. All relays under the hood are new are pull 75 olms per haynes repair manual. ATC control in the dash, with small fan runs but with only 10.5 volt getting to the power supply for all the unit , could it be the relay on the back of the dash module?Dodge intrepid 1995 air conditioning system?
many times the transducer(high pressure sensor) goes bad very very common on all intrepids it's right in the high side line easier to reach from underneath it's cheap and easy and usually the problem