I have a program here that has Latch (OTL) with no (OTU) it works ok. There is more than one in this program. I have RsLogix500 software and a Microligix1500 PLC.

You probably have something that clears the full word e.g clr B3:1 ( or maybe a MOV 0 or a FLL command) somewhere in the program

Thank you, that was it a CLR. Learn somenthing new every day.

Next time if you see one of these, use the cross reference function instead of just a simple search. On a PLC-5/SLC series processor, it will list all references even those that are word/block references, not just bits. The only thing it won't pick up on is indirect and indexed addressing.

When you double clic on B3 file, and then clic on USAGE button, you see all use bit and word. X represent witch bit is used and W in FW column mean full word used.