2018 ABS pump whirring noise when truck is parked

Guys - this morning I hopped in my truck after getting back from work late (so it had been parked for 4.5 hours). I heard some strange whirring noise from the back. It was dark and I was in a hurry so I took a mental note.

Later today, I noticed the same whirring. Went underneath and noticed it seemed to be Part 77730-04010 or something very close to it, near the back left wheel. Pictures attached. This was, again, after being parked about 4 hours.

Is this the ABS module/pump running? Why would it do that four hours later? I was a chemical engineer (not mechanical), this is way over my head. I would think after generating pressure, the ABS pump would not run. Certainly not after being parked for 4 hours. Makes me think there is a leak in my braking system (line leak?).

Anyone had this problem before? Should I take this truck in? It’s less than one month old.

Thanks in advance to everyone.

(there is a similar thread called “2015 Tacoma Noise?” in ‘2nd Gen. forum)

 

The fuel system checks the tank pressure 5 hours after shutoff, it is in the manual I believe

 

Nope. The noise you hear is your emissions system cycling to vent any built up vapors. Totally normal. Very seldom do these trucks randomly break.

 

Page 8 of the manual.

 

Thank you all! I was looking in the "What to do if... (Troubleshooting)" section and Alphabetical Index in the back because I thought it was a problem, not part of the normal operation. You just saved me a trip to the dealer.

 

whew... good to know. I heard this for the 1st time but about 7 hrs later.

 

Man- thank you (again) tacomaworld for keeping me from needlessly worrying about my truck.