Changing pads on a 02 Regal

Were both sides worn down equally ?
Are the rear brakes adjusted up correctly ?
Is the ABS warning light on ?

a warning light like that is normally one of 3 things. all fairly easy to sort out,
1.
blown bulb on brake lights. check and replace bulbs as needed.

2.
low brake fluid level in reservour. check fluid in reservour is up to the maximum mark/line and fill if needed.

3.
the brake pads have worn down to the minimum thickness and need changing.

The light should shut off after the new pads are in and the car cycles through the entire system. If it doesnt, you can still replace them and then just have the dealer or a shop with a scanner reset the light.

Its very similar if not the same. That style Impala uses the same brake and axle assembly as the Regal so you should be in familiar territory once the wheels are off. Good luck!

Pads are easy to be removed ,a 5/8 sockett will loosen the 2 caliper bolt holding it on.they are behind the rotor on the right hand side,(as you are looking at the roror),about 1-2 inches down from the top of the pad for 1,and up about the same distance from the bottom of the caliper for the other.hope it's some help.
Once you find and remove these bolts as is described above the caliper should be rocked front to back and lifted up until it slides off of the rotor. Be careful that you don't pull it hard or drop it once it's loose, there is a brake hose attached that doesn't allow too much travel, It may be weak from age.
This line should be inspected at this time. Once this is in your hand the pads should press out fairly easy. If this is the 1st time your doing this pay careful attention to how the pads are placed. There are also clips that hold them in place, be careful not to damage these.
The front of the caliper will now seperate from the back by sliding off of 2 pins.

Have the rotors resurfaced.. New Pads.. and you'll be OK

check brakes fluid level and also check to see if the sensor was connect back after the pads was change. If all is ok then take it to Auto Zone and they will scan it and clear the code for free also you can clear the code by disconnecting the negative battery lead for 10 seconds but this might make your radio ask for a code in order to play it. good luck

look for a rubber protective cap and remove it. Use an allen wrench to unscrew the pin.

28-DEC-08
Sometimes (when changing the brake calipers on disk brakes, or changing wheel cylinders on drum brake systems) the mechanic will clamp a vise grip pliers on the rubber hose to prevent hydraulic fluid from dripping out.  This can break the internal fiber lining in the rubber hose.  Then the fluid flow can be blocked.  When you press the brake pedal, fluid may not flow to the wheel or wheels.  As you press harder, the fluid may suddenly flow through the line, causing the brakes to suddenly activate.  
Or an even more likely problem, your brakes drag (stay on) and get hot, because the fluid cannot flow back to the master cylinder when you release the brake pedal.  In other words, when you press the brake you force fluid through a partially blocked rubber hose.  But the return of the fluid (backwards through the rubber hose) is caused not by pressure, but just by equilibrium, a balancing act.  Well, if the line (rubber hose) is blocked, the fluid stays in the caliper or wheel cylinder, and the brake is still on, and the brake gets hot.  
Ken   Camas, Washington [email protected]

Its easier than you think. To open the caliper you simply apply pressure and turn the piston, like screwing it in. You must push it in at the same time or it doesn't work.