Rear Bumper Sensor and issues.

folks, i just backed out of my drive way and noticed my rear bumper sensor going off even though there was nothing around me, i stopped and wiped both sensors off and its still doing it but again only when i back up. Can someone help me out as i'm not sure what to do, do you reset them, get new ones and if so how do you know which one to get and what can i expect to pay for one?
its on my 2017 Tundra Crewmax with 36,000 miles on it.
Thanks

 

Is it the rear cross traffic alert going off? If it is sensing something on either side, it will beep at you with nothing behind you. Do you have something on the sides toward the rear?

 

yes you are correct, its the cross traffic alert. once it started i got out and cleaned everything off, i dont see anything wrong with them as it was fine when i parked it last night. i will go back outside and look and see what it does but there was nothing around it earlier when i went to a store.

 

If it rained a lot it can sometimes give false alarms. Once the truck dries well it should return to normal. I have had that happen once and know others that had it happen.

 

its strange that you mention rain, i pulled it into the garage last night however part of the rear end sticks out and water was coming off the house and hitting the cover on the back end of the truck and trickling down the tailgate so that may be it. I will let it dry out and see what happens. We are about to get a "little" rain from Zeta here in South MS so may take a few days. LOL.
Thanks for all the input folks.