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Hi, New to the forum and pretty new to PLC programming. I took the 3-day Sysmac training a couple months ago, but just recently set up one of the NX1P2 units that we'll eventually use for a robotics application. Right now I've got it set up just to experiment with, so I have 3 physical switches (1 momentary, the other 2 toggle) and 4 indicator lights hooked up. Ladder program is set up to light up different LED's when the momentary contact switch  I_SW1  is pressed, based on the position of the other 2 switches. Here's the issue:  When both of the toggle switches are ON (see lines 4 thru 8), all of the LED's light up as expected as soon as the momentary switch I_SW1 is pressed. However, if either or both of the toggle switches are OFF (see lines 0 thru 3), even though it seems like the logic is correct, nothing happens on the output. Lines 0&1 were modified as shown to see if using the variable O_Light1 instead of going directly to O_L1 output would work, but it didn't make any difference.   See attached images for example of working and not working ladder sections as the momentary switch is pressed. In the "working" image, both the toggle switches are on. In the "not working" image, both toggle switches are off. PLC's input & output indicator lights match what Sysmac is showing in the monitor screen, so I'm pretty sure it's in the ladder logic and not the physical wiring.   Thanks for any advice.