Does this model brakes front and rear at the same time when we press just front break ?

Replace the rear brake hose/s. They deteriorate on the inside and clog up. Not letting the calipers or cylinders to release. I recommend replacing the front and rear.

I believe the bleeding pattern for any vehicle is furthest from the master cylinder first and so on the xb it would be rear pass 1st, rear driver 2nd, front pass. 3rd, and front driver last.

Sound like you either have air in the system or a leak. Make sure all the connections are tight on the new calipers. clean off all the connections and blessed screws with brake cleaner. Then have your partner press on the brake pedal while you look for leaks. Reblead the entire system again starting at the right rear, than the left rear, than the right front, and finally the left front. Continue bleeding at each wheel until no air comes out. make sure you don,t let the master cylinder go dry. It will take several pedal pumps for the caliper pistons to take up the gap in between the pads and rotors. I assume you have a helper pushing on the brake pedal during the bedding process?

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The rear brake has a pressure switch that turns the rear brake light on and off. If it's working correctly with the front brake, this switch is the first place I'd go to. Make sure the wires a firmly plugged onto it.

You can find the switch by following the metal line that comes out of the rear of the rear brake mastercylinder. It'll have two wires connected to it.

The rear of the resivoir is for the front brakes. Look for moisture behind the tires if you press the brakes while still. you either blew a line or a caliper has blown

You need to bleed the whole system. Once this is done it should work better. Make sure you are not low on brake fluid. If the front brakes are disk brakes and the rear are drum breaks, the front really does most of the stopping, the back jjust keeps the car from spinning or swaying. But the main stopping power is in the front breaks. They need to be bled correctly, make sure brake fluid is up and make sure emergency break is not engaged. The emergency break uses a lever and cable to activate the rear brakes. The emergency breaks don't run off brake fluid...

please give good ratings, they are very important...

i would check front and rear brakes if rears are drum brakes i would inspect springs and hardware making sure everthing is conected and in place also make sure they are adjusted properly in the front and if rear disc i would make sure to grease caliper slides these allow caliper to move and its important that all moving brake parts are free push caliper pistons in alittle to see if they are sized or not booster is ok and most of the time when master goes it will leak where it meets booster and you will have a low brake pedal or no brakes

The taillight should be on at all times. The brakelight should come on when the front or rear brakes are applied. Start by disconnecting the front brake light switch then the rear to see which switch is broken. Also check the bulbs. I have seen them short out internally. The filament inside the bulb break and contacts the other circuit.

did you change the front, back or both. if it was just the front then you need to put new back brakes in because that's were most of your brake pedal feel comes from. if it was both i would start looking at your brake system to see were the rear brake adjustment valve is and then start fiddling with it till it feels better.

you need to open the caliper bleader valve and release the preasure out of the line. so that the brakes will retrat against the caliber. than you should be able to put them on the rotor. they might be a little snug but they will go on. than close the caliber. now you need to blead the brakes.
1a.Make sure that there is brake fluid in the resivoir.
1b.start the car and have it running until all the brakes have been blead up.
2.Go to the passengers rear and lossen the bleader valve.
3.have someone press the break until you see a steady flow of break fluid comeing out of the line.
4.once that has happend have them press the brake again and hold it to the floor.
5. tighten the bleader valve.
6.go to the drivers rear and follow steps 1-5 again
7.go to the passangers front follow steps 1-5 again
8. go to the driver side front and follow 1-5 again.
you might have to turn the wheel so the person can reach the bleader vavle up front.
Remember to check you fluid after every time you finish with a brake so you do not runn out of fluid and put more air into the lines..... also remeber to alway start with the brake farthest away from the resivoir. you always do them in order 1passanger rear2.drivers rear 3.passangers front. 4. drivers front.
if you need further assistance please let me know