Several possibilities; worn brake pads, worn brake rotors (discs) - do you only hear or notice the grinding noise when applying the brakes? if yes, then most likely either (or both) these problems.
The oxygen sensor for Circuit 2 Bank 2 is located on the rear cylinder bank (cylinders 4-5-6) exhaust pipe - downstream of the catalytic converter. Most easily accessed from underneath the vehicle.
Try the many on-line auto parts sources, such as; www.RockAuto.com or www.autopartswarehouse.com for the replacement parts.

Pull them out, return them for refund and go purchase the original Honda OE pads (at the dealer) for the add'l money. I would not use any pad except a genuine Honda pad on any Honda product. It is possible that you have another issue at work here, like a frozen caliper but I doubt it as the car is not old and Honda calipers are reliable.

Use the 'Estimate Cost' feature on the AutoMD website to gain a rough estimate. Try the 'Find-A-Shop' feature to locate a repair shop for this work in your area.

it probably means you need to get your brakes looked at.

Check the brake power booster, have a helper to pump the brakes and listen it to the vacuum leaks.
Leaks are the No. 1 culprit in having to replace units for brake boosters.

Rotors should last 100K miles easily, unless they get warped due to heat. Timing belt gets replaced every 60K miles if you drive in temps under 20F and over 110F regularly. Otherwise, every 110K miles.

Probably the ABS sensors being shaken by the hit. Im online, i can only speculate. Theres no way i can find out what the problem is for real without looking at it personally.

You must be have your foot on the brake pedal to know/feel when your ABS is on. When u hit a pot hole, your tire momentarily loses grip with the road surface and hops "on air" for a bit. Its probably just a vibration (jolt) you feel from uneven road surface ( pot hole). ABS system is only engaged during braking, to prevent brake lockup during slippery conditions (water, snow, ice ).

Sounds like your problem may be worpped brake rotors, have them checked by your machanic or tire shop. You can't see worpped rotors, don't go by the fact that you change them a year ago. I take it you only get the virbration when braking? get back to me and good luck with it.

They are easy to take off and most parts stores can check them for you . And most times you can buy new ones for not much more than the cost of turning the ones you got .

There is no rule of thumb. The rotors have a minimum thickness and runout spec. Sometimes you can judge the rotor wear by the lip on the end, and you can judge runout by vibrations.

Well, the new brake pads are thicker and might still be rubbing against the rotor, either that or didnt install them properly and is still wedging against the rotor. Or you might have sticking calipers.

Raise and safely support the vehicle. Remove the rear wheels.
Remove the brake caliper mounting bolts and remove the caliper without disconnecting the brake fluid line. Support the caliper so it does not hang on the brake line.
Remove the brake pads and retaining clips from the caliper.
If equipped with caliper-activated parking brakes; use tool J-37617 or equivalent, to rotate the piston clockwise until it retracts into the bore. Align the notches of the piston face so the centerline of the notches is perpendicular to the centerline of the mounting bosses.

To install:

Install the new brake pads and clips in the caliper and install the caliper in the mounting bracket.
Tighten the caliper mounting bolts to 12-17 ft. lbs. (16-24 Nm), or 32 ft. lbs. (43 Nm) on vehicles with shoe-type parking brakes.
Install the rear wheels. Check the brake fluid level.
Pump the brake pedal until pressure is felt before moving the vehicle.

For additional information, see this ................. http://www.autozone.com/.../...rGuideContent.jsp