breaks failed then began working again

My breaks failed ccompletly then worked again

My car has 135000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hello, thank you for writing in. The brakes can fail for several reasons, and without much information as to what year and model your vehicle is, it is hard to tell if the ABS system was a factor. While this system can take control of the brakes momentarily to assist in an issue that has been detected, it should not have happened without cause. If the vehicle was having issues with the hydraulics, you will want to inspect for any signs of leaks. This may mean a wet spot, rust, or low brake fluid. A full inspection of the brakes needs to be done regardless. For more help with the inspection, contact our service department to schedule an appointment.

How to Identify and Fix Common car Problems ?

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This can be due to a number of problems: a leak in a brake line, a loss of pressure within the master cylinder itself due to a failed seal, or air being introduced into the braking system.
Yes it can , happened to a friend while I was in the car , the brake pedal went to the floor and he ran the car into the shed door, after backing the car a way from the door the brakes worked fine , Me being a mechanic for many years decided there was a fault in the brake master cylinder ,On dismantling the cylinder I …
A bad master cylinder can fail intermittently, and then regain pressure. A stuck brake or parking brake also can cause this condition by causing your brake fluid to boil and your brakes to fail. But that`s unlikely to happen after only five or six minutes of driving, so I`d lean toward the master cylinder.
One of the most common reasons for your brakes touching the floor would be an issue with your brake fluid. Your fluid being low or air reaching the brake line will prevent the fluid from flowing properly, resulting in a spongy pedal. A bad brake booster is another common cause for a malfunctioning pedal.
The classic symptom of a failing master cylinder is a brake pedal that “dives” or sinks slowly to the floor while pedal pressure is being applied. Another sign to look out for is any leaks around the master cylinder. If a seal is worn out, it may leak past the seal and onto the pushrod that attaches to the brake pedal.
Yes, the braking system can fail suddenly without any indication or warning. However, sudden total failure is very rare. But brake failure is dangerous, and that is the reason why you should maintain the brakes properly.
Intermittent power to the brakes

Most brake booster vacuum pumps are electrically powered. Due to this fact, problems with wiring or internal components can cause this intermittent condition to occur.

Noticing your brakes have failed while driving can be a shocking experience. While you hope it never happens to you, prepare yourself for such a situation by familiarizing yourself with some tips to help you stop as safely as possible.
Yes master cylinders can fail without leakage, the clutch master cylinder has a piston inside and there are separate channels for hi-pressure line and return(low pressure) line and their location in the cylinder differs for manufacturers.
How to stop a vehicle that has total brake failure. Pump the brake pedal continuously. This could build residual pressure in the brake system to slow the car, but will most certainly warn trailing traffic you are attempting to stop. If you feel brake pressure return, gradually press the brakes until you come to a stop.
Fortunately, brake failure is a relatively rare phenomenon, thanks to advances in vehicle design and manufacturing. The National Highway Traffic Safety Administration released a report in 2018 that found that faulty vehicle parts accounted for only 2% of crashes overall, and faulty brakes made up 22% of that 2%.
Usually, your brake pedal will sink if the ABS or master cylinder cannot maintain the proper hydraulic pressure. This inability to maintain hydraulic pressure will not only make your brake pedal sink to the floor, but it will also make it much more difficult to stop your automobile.
Air in the brake line(s) is the most common cause of a soft/spongy brake pedal. If air gets into the brake lines, it can prevent brake fluid from flowing properly, causing the brake pedal to feel spongy or soft. If the brakes are soft or spongy, this is a good time to change or flush the brake fluid.
A bad master cylinder can cause your brakes to fail, which can be extremely dangerous. If you`re experiencing any brake problems, make sure to take your car to a mechanic right away to have it checked out or change the master cylinder yourself.
This pressure travels from the master cylinder, through the brake line, and acts on the brake caliper and brake rotor. However, if air bubbles are in the brake line, hydraulic pressure is reduced, making your entire braking system less effective and your vehicle more difficult to control.
Symptoms of a faulty brake booster

Stiff brake pedal action is a strong indicator of brake booster failure because the booster will have lost its ability to amplify the force of your foot to the brake, requiring you to use more pressure.

Brake pedal difficult to push – The most common sign of a brake booster leak is your brake pedal feeling “harder” than normal. It will require more force to work and increase your stopping distance. If you notice this, you should get your car inspected as soon as possible. This is because it can affect your safety.
Similar to a vibrating steering wheel, pulsating brakes is usually caused by warped rotors. Rotors are constantly being heated up and cooling down when you drive, meaning that they can become easily worn and loose their shape over time.
If brake fluid is leaking into the vacuum booster, the brake fluid can cause the rubber diaphragm to fail in the brake vacuum booster. So it`s possible when fluid is leaking into the brake booster that the brake vacuum booster may need to be replaced.
Use a screwdriver to press and hold the plunger in the rear of the master cylinder. The plunger should be very firm, if not immovable, past a few millimeters. If the plunger keeps moving in, this indicates a fault of at least one of the internal seals.
Corrosion of internal parts due to age and lack of periodic maintenance can also contribute to master cylinder failure. Excessive heat can also cause wear and corrosion, which can lead to brake failure.
Pump the brake pedal fast and hard to build up brake fluid pressure. You will know in three to four pumps if the brakes will work.
The symbol is a circle containing an exclamation mark, and the circle is surrounded on each side by what look like rounded brackets. In some vehicles, there may even be the word `brake` under or next to this.

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My AC does not always work. If I fiddle with the blower knob I can ususally get it to work on the lowest setting.
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It sounds like you may have a faulty blower motor resistor. The highest speed setting may still work because in most cars in the highest fan speed settings the current bypasses the blower motor resistor. In some cars, if the resistor is failed, the fan may stop working completely. Another reason a blower motor resistor may fail is when the blower motor has a mechanical problem or when a foreign object jams the blower motor fan blade and prevents it from spinning freely. This leads to increased current through the resistor and causes it to overheat and fail. I would suggest having an expert from YourMechanic come to your location to diagnose your system to determine what may be causing the fan not to work properly.

breaks failed then began working again
ANSWER : Hello, thank you for writing in. The brakes can fail for several reasons, and without much information as to what year and model your vehicle is, it is hard to tell if the ABS system was a factor. While this system can take control of the brakes momentarily to assist in an issue that has been detected, it should not have happened without cause. If the vehicle was having issues with the hydraulics, you will want to inspect for any signs of leaks. This may mean a wet spot, rust, or low brake fluid. A full inspection of the brakes needs to be done regardless. For more help with the inspection, contact our service department to schedule an appointment.

Why doesnt my brakes work?
ANSWER : Hi there. Driving at highway speeds with the parking brake on most likely overheated the rear brakes, damaging the wheel cylinders, and possibly boiled the brake pedal. That burning smell was from the brake shoes. There is also most likely damage to the brake drums and hardware. The condition of the wheel cylinders will be not be known until a proper inspection has been performed to check the seals for leaks. The brake fluid will need to be checked and determined if it will need to be replaced. I suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist with a brake pedal has to be pumped to work inspection.

All dashboard lights and tail lights do not work after driving through a lot of snow. Headlights work. And brake lights work.
ANSWER : Hello. We’ll be happy to help you. There are a few things that I recommend checking to discover why your lighting system is malfunctioning. The headlight dimmer switch should be checked. Along with the wiring harness above the right front tire behind the fender well cover. Also
the main fuse under the hood should be inspected because other people with your particular vehicle have had similar lighting issues if that fuse goes bad. It will be a great idea to check the rest of the fuses in that area too while checking the main fuse. Once the fuses are checked inside of the main fuse box then I would check the fuses inside of their interior fuse box. The interior fuse box should be located on the driver side of the dashboard near where your legs would be. If you need more assistance with repairing your vehicle please keep in mind that our organization provides Mobile Mechanics who can help you diagnose and repair your vehicle, all at competitive rates.

Honda Civic 2008. AC stopped working suddenly and engine check light came ON for a day.Next day AC worked and no engine light.
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Okay so when I turn my lights on at night my brake lights do not work, when I don’t have my lights on they work fine.
ANSWER : Hi there. Based on your inquiry, it’s highly probable that you have a damaged light switch or some electrical fault inside the turn signal relay. However, it’s also possible that the brake switch above the brake pedal could also be the source of your problem. Due to the fact that multiple electrical components might be causing this issue, it’s a smart idea to first have a professional mobile mechanic complete a brake lights are not working inspection, so they can determine what’s causing all of these issues and recommend the right repairs.