I was looking at obd reader set button next to obd prius gen 3 what is the set button next to obd reader is it a reset I found this part in tray covering obd reader port ,the mechanic who did work might have left there or this is not related to prius ? part has name ZERO and code is VSG210321 ,googled it dont get anything car runs ok
If you're looking at a SET button near the diagnostic port, it is probably the button where you set your desired tire pressure for the tire-pressure monitor. You fill all your tires to the pressure you want, then hold the button and the car remembers that pressure. You can read about it in the owners' manual. If you change your mind about your preferred tire pressure, you can change it and repeat. The "Zero" thing isn't OE, that's for sure.
