Abs brake light on, brake light too, hard pedal, new pads and good rotors, no pressure to rear calipers? Fluid level went low, somewhere, than came back, overflowing after filling. No body can find parts for this 90 lincoln mark vii LSC. Can anybody help? used? let me know... abs pump, master cyl., accummulator, switches, sensors, etc..., etc...

and start off at the caliber farthest from the master cylinder. usually right rear. If your peddle stays rock hard there's still still air bubbles in the hydraulic fluid an your lines.

Try bleeding some brake fluid on that side. You may have a blockage. Also check if the rotor is in good condition, it may be warped. Good luck!

An internally collapsed brake line near the caliper, the flexible line, can let the brake fluid pressure go into the caliper but restrict it from returning and releasing the piston in the caliper.

For some reason these vehicles you need to bleed brakes several times, had same problem, so air hangs up in lines somewhere it apears. When you say brakes sticks, describe it better, locked up, or dragging on rotors?
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Its possible that your rubber lines are collapsed. I've had them keep fluid from going thru as well as not releasing pressure. See if fluid gets to caliper thru rubber. You can plug it with your finger and release pedal. If you feel vacuum and fluid flows well when you push brake, that's probably not the problem. Its somewhere to start tho.

FIRST REMOVE SMALL AMOUNT OF BRAKE FLUID FROM THE BRAKE MASTERCYLINDER. THEN USE A LARGE C - CLAMP AND LEAVE THE OLD BRAKE PAD IN PLACE ON PISTON SIDE THEN COMPRESS THE PISTON IN CALIPER BORE. IF YOU SEE SIGNS OF BRAKE FLUID LEAKING AROUND PISTON SEAL.THE BRAKE CALIPER NEED REPLACING.WHEN YOU FINISH BRAKE JOB NEW BRAKE SHOES IN PLACE MAKE SURE BRAKE MASTERCYLINDER COVER BACK ON MASTERCYLINER THEN PUMP BRAKE PEDAL UNTIL NEW BRAKE PADS SEAT AGAINST BRAKE ROTOR.CHECK BRAKE FLUID LEVEL IN MASTERCYLINDER MAKE SURE ITS NOT LOW.

Removal & Installation Front To Remove:

1. Inspect the fluid level in the master cylinder reservoir. Remove fluid from the reservoir until the level is lower then half way between the MAX and MIN levels.
2. Remove the tire and wheel assembly.
3. Install 2 wheel nuts to secure the rotor on the hub.
4. Remove the bottom brake caliper pin bolt.
5. Pivot the brake caliper body upward and secure out of the way. Do NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Compress the piston back into the bore using a C-clamp. Figure of brake assembly with caliper raised showing brake pads in mounting bracket
   
   
7. Remove the inboard and outboard brake pads from the brake caliper bracket.

To Install:

1. Install the brake pad retainers and both brake pads into the caliper bracket.
2. Pivot the brake caliper down over the brake pads and into the brake caliper bracket. Insert the lower brake caliper pin bolt and torque bolt to 70 ft-lb. (95 Nm).
3. Reinstall the tire and wheel assembly.
4. Lower the vehicle.
5. Refill the master cylinder. Pump the brake pedal several times to seat the pads against the rotor.
6. Check the master cylinder level and add fluid as necessary.

Rear To Remove:
Rear disc pads R&I

1. Inspect the fluid level in the master cylinder reservoir. Remove fluid from the reservoir until the level is lower then half way between the MAX and MIN levels.
2. Remove the tire and wheel assembly.
3. Install 2 wheel nuts to secure the rotor on the hub.
4. Remove the upper caliper mounting bolt.
5. Pivot the caliper down to access the pads.
6. Remove the inboard and outboard pads from the caliper bracket.
7. Remove the brake pad clips from the caliper bracket.
8. Compress the piston back into the bore using a C-clamp and the old inner pad.

To Install:

1. Install new brake clips in the caliper bracket.
2. Install the inboard and outboard pads in the caliper bracket.
3. Pivot the caliper up over the pads.
4. Reinstall the upper mounting bolt and tighten to 32 ft. lbs. (44 Nm).
5. Remove the 2 wheel nuts securing the rotor.
6. Reinstall the tire and wheel assembly.
7. Refill the master cylinder. Pump the brake pedal several times to seat the pads against the rotor.
8. Check the master cylinder level and add fluid as necessary.

possible dirty/defective wheel sensors (typical), or faulty ABS actuator.

Most likely time for some new pads/shoes and check rotors/drums

The things you should check are:

1. Fluid level in the master cylinder, if this is low you have a leak somewhere and it needs to be fixed, if it is a '96 it could have a leak in a caliper seal or a wheel cylinder and it would be tough to see.

2. If it has been a while since you have changed them check your pads/rotors for wear

3. If the pads are good, bleed the air out of the system. however air in the system usually causes the pedal to feel "spongy" and not just sink to the floor

Sounds like need new Calipers for front too. Maybe a new master cylinder may be need too. Sound like to Calipers or master cylinder are now letting to brake fluid go back to the master cylinder.