A couple days ago I acquired a 2003 Santa Fe that had been sitting for almost 3yr. Chnaged the oil, added fresh fuel and some stabilizer, and installed a new battery. It started without to much trouble and I was surprised that almost every feature on the vehicle worked right away.
I had to free up the sunroof and reinstall the instrument light dimmer switch and i replaced all 3 wiper blades. The engine has a runabikity problem that I think is the IAC connector and i have orders a new connector. The windshield washer pump doesn't work and I haven't spent any time on that issue yet.

I checked the brakes and the front inner pads were approximately 35% so I replaced them and everything was fine.
The rear brake pads were down to less than 15% so I am replacing those as well.
.......and here is the problem. I couldn't get the right rear caliper to compress and bent a large C-clamp trying to make it collapse.
I didn't realize that they needed to be rotated.
I purchased a new caliper with mount and insatlled it with a copper washer betweem the caliper and hose and onebetween the hose and bolt. I didn't have anyone to help me bleed the system and I was able to get the pedal pretty solid but not perfect. I replaced the pads on the other side without issue. The caliper compressed with very little effort from the c-clamp.
The pedal had been high and hard after bleeding the system prior to putting pads on the drivers side rear, but when I was done the pedal was going to the floor, the brake warning light was on and the 4x4 light was flashing. The master cylinder was down a little as of there was a fluid leak but I could not see a leak. The abs motor made a couple fluttering noises and I could not get the brakes to pump up and feel like they should.
I did not see that I had damaged either of the rear abs sensors but am concered about the 4x4 light flashing and the soft pedal.
I will have a second person help me bleed the brakes tomorrow, but i dont know why they went from feeling very firm with a high pedal to hitting the floor with the warning light staying on.

Any help or information on the 4x4 light flashing after the pad replacement would be much appreciated.

Thank you......

 

There are a few things of which you should be aware.

First- you need to make sure the area around the caliper piston is CLEAN , then open the bleeder when compressing the piston back into the caliper so the dirty fluid is expelled..
If at any time the brake pedal is allowed to go to the floor, in normal use the pedal only travels so far and stops, abrasive particles build up in the master cyl bore and when the pedal goes to the floor, that material damages the rubber cups in the master cyl and now the master needs to be replaced because it now leaks internally.

A soft brake pedal is caused by air trapped in the hydraulic brake system and with an ABS, (anti lock brake system) a scan tool is required to operate the solenoids in the hydraulic control unit to allow that air to pass through the solenoids on out to where it can be removed by bleeding .. There is more to today's brake systems than in the old days of just replacing parts.

I should mention ,,,,if the bleeder screws on the caliper get rusted in position you could wind up replacing calipers because if the bleeder screw breaks off attempting to open it caliper replacement is now required.

 

As I said in the post, the left rear caliper is fine, i had to replace the right rear caliper because it would not compress enough to fit around the new brake pads. The master cylinder was never more tham ¼ cup low. I am still unsure if the caliper pistons need rotated as they compress. The drivers side compressed smoth with no issues and I did not rotate it. The front calipers compressed with my thumbs....but the right rear just wouldn't. I know trying to bleed brakes with something wedged between the pedal and seat isn't very effective, but i didnt have vacuum pump or another person. I would get a really decent feeling pedal and then try to get the last bit of air to spurt out and I'd loose the firm pedal. Very frustrating. It wouldn't gravity bleed at a noticeable rate either. And I understand fully the difference in replacing parts and strategy based diagnosis. I'm a former dealership fixed op manager and ASE Certified on brakes, among others.
And on any 2003 vehicle I've eve seen you certainly should be able to replace a caliper without a scan tool.
I posted here because this is my first Hyundai vehiclr and I thought maybe there was a sensitive part that I may have damaged trying to compress the stuck caliper......or maybe there was a service procedure that is specific to this model or to Hyundai.
Ans yes, i know that a stripped bleeder screw can necessitate a caliper replacement.

 

Welcome to the ASE club.
Pretty sure you as I don't mind an occasional reminder. We realize the more we learn , the more we don't know.
Glad to have you aboard and appreciate your assistance helping forum members, thanks.