Rack pump down help

[Freezon]

Good evening, I have a rack that I service. Have been for 6 or 7 years and for the most part it works pretty well. It was just upgraded to a newer computor system . Lately, It has been logging an error code that it has failed to pump down. I am asking for guidance here, would it be the suction "sensor" that tells the computor it has reached the predetermined cut out set point or the low pressure cut out control located on one of the 5 compressors? or possibly none of the above? Thank you in advance

[Brian_UK]

It seems that you need a copy of the software logic diagram of the new system.

Simple speculation can make you waste a lot of time and energy searching for the answer when someone else has already made the choice.