Fooling a MAD would likely be the same as fooling a camera, one action per combat turn to edit a file. This shouldn't be too hard for a decker to hack and walk-through the device, even without improved reflexes.
[quote="SR5 Page239] If you want to perform a continuous edit, such as removing your teammates from a video feed, you need to perform this action once per Combat Turn for as long as you want to keep the edit going.
So as I was walking into the scanner Id say to my GM that I want to continuously edit the file that would detect my weapons inside? Though I thought Kincaid said weapons wouldn't be detected, just the arms since they're uh...not flesh lol. But that tidbit does help me, thanks!
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A MAD will detect your arms, but whether or not it can parse your metal arm from the metal gun inside it is up to the GM. It would probably be a bad idea to spoof the MAD with obvious cyberarms, since that'll tip off the guards that's something is wrong with the scanner. It may still be worth your while to mess with the MAD for the sake of your teammates. Doing a continuous edit on a MAD you're planning on walking through will require you to be in AR, so keep that in mind too.
I wouldn't be too worried about MADs with this guy, to be honest. You'll set them off and point to your arms. As long as you're not carrying a normal gun or something, you should be okay. The thing to watch for is an olfactory scanner, which can sniff the ammo in your arm. Those are less common than MADs, but something I'd definitely hack.
IMPORTANT EDIT: I realized for the last few posts I've been confusing MADs with millimeter wave scanners (aka cyberware scanners). A MAD will pick up any metal with a single hit, but that's all it does. You have obvious cyberarms so they're essentially meaningless. The thing that picks out specific items of cyberware is the millimeter wave scanner, which has different thresholds based on the number of implants and their grade. There's a case to be made that cyberguns are accessories, not augmentations, so the wave scanner won't be able to distinguish them from the arm. Chem sniffers are still trouble.