my 2007 silverado classic 5.3 crew cab 4x4 i had a leak in radiator, so I replace the radiator, decided to also replace the waterpump, thermostat, upper and lower hoses, all good \. then notice that the two cooling fans were not running nor was the compressor. bought the compressor, actuator and orfice had a shop install vacuate and recharge system at idle AC blowing out 52 degrees both fans working, as soon as you put truck in reverse compressor starts to work intermittently turns on for a split second then off , both fans turn off , shop could not figure out problem , this from the mechanic replace the high pressure switch connector and it still acting same way, The ECU sees the request but will randomly turn the compressor off. He recommend taking it to dealer might be a reprogram issue. Any suggestions, help,, what might be going on . Things I can try

Thanks in advance

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