If a 2017 RAV4's touch screen is not working, what coould be the cause?

I'm going to need more information about what's not working on Your 2017 Toyota RAV4's touchscreen to be able to help You: that's just ambiguous. Does it not turn on Are You seeing distortion Is it making noise Do You have a display, but it doesn't register it when You touch it I'll assume that You mean You've got nothing there, at all. First, You're going to want to check the fuse for the infotainment system, which is located in Your interior cabin fuse boxAnd clearly labeled in there. See if You've got any burnt. Next is going to be a power issue; make sure Your battery is fully charged, though if Your vehicle's on, this is less of an indicator; wiring, though, is often the culprit. For various reasons, wires are compromised, resulting in no power to the display. There haven't been any particular LCD problems with the RAV4, but that doesn't preclude it failing early. Finally, it's possible this is just a software glitch: Try resetting Your Toy's ECU and see if the display comes back. If none of that works, it's time to call the dealer.