You most probably have air in your brake lines. You can bleed the air out with the help of an assistant. There should be a bleeder screw located somewhere on the brake back of the caliper. Loosen this srew as your assistant presses the brake pedal (make sure your assistant does not let up on the pedal). As soon as the fluid is clear of air bubbles, tighten the screw snugly (do not overtighten (could break). Repeat these steps for the opposite side. Hope this helps.
There is still air in the system.
Check the petal and make sure that the plastic part that touches the brake light switch when the petal is in contact with the brake light switch is still on the petal, if it is missing you will need to replace it, so the petal will make correct contact with the brake light switch.
Air in the brake lines
you dont you bleed and adjust the brakes
The Brake booster needs replaced
bleed your brakes again...there's air in the lines
You need to inspect the brake pads/shoes and have the brake system bled. The soft pedal is air in the brake system. The fact that you are hearing air makes me suspect you may have a defective brake booster. Have the power brake booster vacuum diaphragm inspected.
You need to bleed the brakes. Loosen the bleeder valve on one of the calipers and have someone press and hold the brake pedal. Tighten the valve and release the brake pedal. (If you let off of the pedal with the valve loose, air will be drawn into the system and make the problem worse.)
1) Con a helper into helping you. 2) Open the bleeder valve on the brake cylinder. 3) Have your helper press on the brake petal. 4) Close the bleeder valve when air stops or when the petal is floored. 5) Have your helper release the brake the petal. 6) Check the fluid level in the master cylinder. If it goes dry you will have to start all over. 7) Repeat 2-7 until you stop getting air from the brake system.
Only if the bulb or wire is burnt out... Else the switch has defect,,
This is caused by the pressure release in the brake lines when you retract the pistons in the brake calipers to accommodate the new brake pads that are thicker than the ones that are removed.
vacuum leak at the master cylinder or vacuum line to the master cylinder