TAC50 Question

I have a question regarding TAC50 Card Cage. My DSP board, EEPROM and PMI 4 board are all failing the go/no-go test. Sent them to Access and they said they all tested good and spun up a motor. I reinstalled them and get the same results. I checked my 12 VDC on the backplane and have nothing. It says the 12V comes from PS1 along with the 5V, but I cannot find anywhere to measure the 12V on PS1. My 5V is good. I also don't see in the prints for the power supplies where the 12V comes from PS1, only the 5V. Am I missing something? Is PS1 bad? Or is the backplane bad? I tried to measure the 12V on the other TAC50 controller that is running and also get no 12V on the backplane test point.

Any help is appreciated. Thanks

Tac50 did away with the 12v. Only T3/T4. Try pulling every other board in the rack one by one until you find one that when removed is the only no-go in the rack. That is the bad board.