When I Google P0340 Toyota I get:
Code P0340 indicates there is a problem with the electrical wiring of the circuit attached to the camshaft position sensor. This issue can result in the display of a multitude of other codes that relate directly to your vehicle's camshaft. In addition, your powertrain control module (PCM) could also be damaged.
If it were me I would have it towed to a dealership or trusted local garage and get a good diagnosis. Then I would decide if it were something I could handle or not. If you have AAA you can get the tow there and back for free, probably. You'll owe the garage about an hour for diagnosis.
Others will chime in here and offer more/better advice, but that's what I would do. Good luck.
