@ToledoEd posted:John, only one TIU. I’ll check the signal. Would it matter that the track power runs out of the tiu through a fuse to the track? The test track bypassed the fuse. I have no problems with my PS3 engines. I put a PS/3 on the same track with the PS/2 then powered up the track. PS/3 started up. PS/2, nothing.
As long as the polarity is correct, the fuse is insignificant. Alan may be onto something, check to see if track polarity is proper.