Tac50 with dsd412 drive dc

I’ve got a tac 50 with dsd412 drive dc installed in 2000 I’m getting a 403/406 drive fault and 24/56 controller fault check replaced modules checked a lot of this but call keeps coming back in ???

Does it stall on a re-level maybe?

Hi there just want to post that I was able to find the problem I found a bad pmi module card in slot number #2 still waiting on replacement 6300cnf module card