Can’t Push Brake Down to Start Car

As I sat in my car, eager to get on the road, I pressed down on the brake pedal, only to find that it wouldn’t budge. My foot applied more pressure. But still, the pedal remained stubbornly in place. Panic started to set in. What could be causing this? How much will this cost me?

If you find it hard to press the brake pedal to start the car, reasons include an exhausted brake vacuum, a damaged ignition switch, low battery power, a blown ignition fuse, or a faulty starter cable. These issues are simple to identify and fix on your own.

After a bit of research and investigation, I found the answer to my problem and fixed it myself. Whether you’re a seasoned driver or a new car owner, this information could save you time, money, and a whole lot of stress.

So, let’s dive in and get to the bottom of this brake pedal mystery!

Cause	Diagnosis	Fix
Exhausted brake vacuum	Inspect the vacuum hose and the check valve Deplete vacuum if necessary	Fix any issues with the hose and valve or replace them if needed
Damaged ignition switch	Check for power using a test light Check three circuits of the ignition key	Replace the switch
Low battery power	Measure voltage with a multimeter Clean the terminals if corroded	Try charging the battery or replace it if necessary
Blown ignition fuse	Watch physically for signs Check by multimeter	Replace the blown fuse

 Let’s dive deep into causes, diagnostics, and solutions.

Exhausted Brake Vacuum

Most newer vehicles include power assist, which uses a brake vacuum to function. If you applied brake pressure with the engine off, you might have used up the vehicle’s reserve vacuum. The brake pedal will feel harsh as a result.

How I Diagnosed and Fixed Vacuum Brake Booster?

As I suspect my brake booster is causing a hard brake pedal, these are the observations I have made to confirm it.

First, I inspected the vacuum hose going to the intake manifold. I made sure there were no cracks or leaks.

Then I removed the check valve and listened for a hiss. I didn’t hear any hiss.

Note: If you hear one, it could indicate a leak in the vacuum hose.

Next, I started the engine and made sure there were no restrictions on the vacuum hose going to the intake manifold.

After I checked the check valve itself, The air should flow one way and not the other. I tried blowing air through it, and it did not allow air to pass through. So, there wasn’t any problem associated with the brake vacuum.

Note: If you find any issues with the vacuum hose or check valve, make the necessary repairs or replacements.

As there weren’t any issues, I depleted any remaining or reserve vacuum from the booster by depressing the pedal six or seven times until I felt the brake pedal hard.

Then I started the vehicle and observed the pedal. Successful! I felt a much softer pedal.

Watch this video to understand these steps much better.

If vacuum booster fixing does not solve the issue, the stiff brake pedal and not starting the car may be completely separate problems. Following are the reasons, diagnostics, and fixes you can make on your own for not starting the car. These are simple fixes, and you can do them on your own.

Damaged Ignition Switch

Your ignition switch may be failing if your automobile is older. Flickering dashboard lights and a slow-starting engine are indications of a broken ignition switch. Put your brakes on and look for your brake lights to test your ignition switch. If you don’t see any brake lights, the problem is probably with your ignition.

Ignition switches may be fixed quickly and affordably. Either do it yourself or get a mechanic to replace it.

How To Diagnose the Ignition Switch?

First, Remove the screws from the bottom of the steering column cover and pull it out of the way.

Then, Remove the top of the cover to reveal the end of the ignition switch and its electrical components.

Check for power using a test light and ensure that all connectors have voltage.

Then check the three circuits of the key. If all circuits have power, even when the key is turned off, this indicates that the ignition switch is gone and needs to be replaced.

How To Fix a Bad Ignition Switch?

Replacing it is the best option. There’s nothing to worry about; ignition switches are much cheaper.

So, unscrew the screw holding the switch assembly in place and unplug it from the wiring harness.

Then, install the new ignition switch by snapping it in and securing it with a screw.

Test the new switch by turning the key and ensuring that all circuits have power or ground, as appropriate.

After confirming the new switch, reassemble the plastic cover assembly and screw the two halves together.

Finally, test the car to ensure that the ignition switch is working properly.

Low Battery Power

Your car’s battery may abruptly fail or start to lose power, which might cause the brakes to become jammed. A stationary car’s battery voltage should be 12.5 volts on average. When it is lower than that, the car’s dash lights could start acting strangely or eventually turn off.

How to Diagnose car battery?

First, turn on the headlights for two minutes to remove any surface charge from the battery.

Set the multimeter to 20 volts or higher.

After that, join the multimeter’s positive (red) lead to the battery’s positive terminal and its negative (black) lead to negative terminal.

The voltage reading on the multimeter should be around 12.6 volts. A reading of 12.0 volts or lower indicates a weak battery.

Check the battery terminals for corrosion if the battery is ok.

If there is any corrosion, clean the terminals with sandpaper and tighten them securely.

How To Fix a Bad Battery?

If the multimeter reading is above 10.5 volts, charge your battery using a battery charger. It will fix the battery. But, if the reading is below 10.5 V, sadly, the battery is completely dead. You have to replace the battery.

Blown Ignition Fuse

You won’t be able to start your car when a fuse in it has blown.  Fuse replacement is required when the connection between the two terminals breaks down, indicating the need for a new fuse.

How To Diagnose Ignition Fuse?

First, find the ignition fuse. You can find it by using the diagram on the fuse box cover. You can easily identify a blown fuse by visual inspection. Check if the fuse looks intact or if there is a missing section inside.

How To Fix If Ignition Fuse Blown?

You have to replace the fuse. Fuses are very cheap. Keep in mind to replace a fuse with the same amperage.

Faulty Starter Cable

If your starter cable accidentally gets separated from the battery terminal, your brakes can get stiff.

Note: If you hear loud clicking noises when you turn the key, your starter motor may malfunction or be dead.

You can check and fix it yourself if you feel confident doing so. If not, get a mechanic.

FREQUENTLY ASKED QUESTIONS (FAQs):

What to do if brakes won’t release?

You have a few options for unsticking a brake. If it’s safe to do so, you might try manually reaching under the car to yank the wires or shaking the car back and forth. To disengage the brakes, you can also try repeatedly setting and releasing the brake.

How do the brakes on a car work?

When you depress the brake pedal, hydraulic wheel cylinders push the two curved brake shoes. Each of them has a friction material lining against the interior of a rotating brake drum. This contact results in friction, which permits the vehicle to stop or slow down.

Do all cars have emergency brakes?

Yes, it is a requirement by law. The emergency brake, also known as the parking brake, is designed to keep the vehicle stationary when parked. The emergency brake can also help stop the car in an emergency if the main brake system fails, in addition to its use for parking.

Where are the brake pads on a car?

The car’s brake pads are usually located inside the brake caliper, which is mounted around the rotor. When you press the brake pedal, the hydraulic pressure generated causes the caliper to squeeze the pads against the rotor. The pads are made of a composite material that wears down over time and needs to be replaced periodically.

Conclusion

I hope you understand why you can’t push brake down to start car. You can diagnose and fix these problems yourself, saving you time and money while gaining valuable knowledge for free.