Hey guys, i have a tac20 that is shutdown on bottom landing. IMS does not communicate with CPU when connected. i have used IMS on this car before with no problems. what i know is that the car won't run on inspection and my safeties are made.
Any suggestions would be appreciated.

Do you have wd?

From the beginning;
Three phase power present? Glass fuses good? Pico fuses good? Does it have battery lowering? If it does, unplug it from the controller supply and bypass the ELD altogether to check. As lowoil asked, "do you show any LED's in the controller"? I ask these simple questions because you haven't told us much about your problem other than the obvious..." It don't work"