Brake warning light comes on intermittently when I accelerate or drive uphill

The brake warning light stays on all the time. I've checked that the emergency brake is not on. There are no noises or smells. What do you suggest is the problem?
Experienced mechanics share their insights in answering this question :
Check the brake fluid level. If the level is low, it will illuminate the "Brake" light. Many time as the brake linings wears, the level of fluids will drop to keep the pads close to the rotor. If the fluid is low, the brake linings and the brake hydraulic system should be checked for leaks. You may want to enlist the help of a mechanic, such as one from YourMechanic, to inspect and recommend repairs to the brake system.

How to Identify and Fix Common car Problems ?

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When your brake light comes on, your car is letting you know that either your vehicle is low on brake fluid, the emergency brake is activated, there`s trouble within the ABS unit, or there`s a problem with the sensors.
Typically, your brake system warning light being on means your parking brake is engaged, but if you`re still seeing the red (or orange) warning on your dash while the parking brake is disengaged, you will need to get your brakes inspected as soon as possible.
It illuminates to show that the parking brake or emergency brake is engaged and must be released before driving. If it remains lit after the parking brake is released or if it turns on and off intermittently while you`re driving, it means you need to add brake fluid.
This is a known problem with this vehicle related to a faulty brake master cylinder. The symptoms are very similar to what you are describing in that the brakes will feel as if they are being applied when the car is accelerating.
It is also common for a driver`s foot to slip from the brake pedal onto the accelerator or for a driver to errantly apply pressure to both the brake and accelerator pedals at the same time. The result can be a rapid acceleration of the vehicle, often at full-throttle, when the driver was expecting the vehicle to stop.
Parking brake does not hold car properly

The most common symptom of a problem with the parking brake cable is a parking brake that does not properly hold the vehicle. If the parking brake cable becomes excessively worn or stretched, it will not be able to pull the the parking brake as tightly.

When your brake fluid is low or if there are any brake leaks, it will cause the brake light to turn on. It`s important to have this checked out right away because if all fluid has leaked, your brakes won`t have the ability to stop.
Faulty Switch: One common reason for the Parking Brake light to stay on is a failing or failed switch. This can be checked easily by moving the handle to and fro after it is down. If the light turns off (or turns off and then back on), the switch is the most likely culprit and will need to be replaced.
Worn suspension or misalignment is a common diagnosis, as well as damage to the steering components. If you have not replaced your tires for a while, or if they wore out unevenly due to an alignment problem, that also creates a pulling sensation, as your car does not travel smoothly.
Caliper pistons can become stuck in their bore, and when this happens the car will usually pull to one side when the brakes are applied or the pads and rotors will be overheated or worn down too fast. It will also affect performance under acceleration as the brake is sticking.
Throttle-braking

In a rear wheel drive vehicle, greater throttle usage while braking will counteract the rear braking force and move the brake bias forward.

If your accelerator were to stick it would most likely be caused by a floor mat or other object getting jammed under the gas pedal. This could obviously be avoided by keeping your vehicle clear of clutter and making sure floor mats are properly fixed in place.
Press and hold the EPB switch until the brake warning light on the instrument panel starts to flash. Continue to hold the switch until the flash goes off. 4. Release the switch and press it again, the parking brake should now be reset.
If the brake warning light comes on while you are in traffic or driving, don`t panic. Your vehicle has more than one hydraulic braking system. So, while it may take a little longer to come to a complete stop than usual, safely pull over and have your vehicle towed to your home or to a trusted mechanic to inspect.
While it may seem like putting the car in “Park” is enough, constant use of the parking pawl can wear out both the pawl and your transmission (especially if you frequently park on steep inclines).
If the dashboard light remains on, it`s telling you that thre is a brake system problem that could prevent you from stopping your vehicle. Turn off the engine and arrange to have the vehicle transported to your trusted mechanic.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

When I put my foot on the brake my back left brake light goes off, when I take it off the brake the brake light comes on
ANSWER : I would suggest trying to disconnect and reconnect the wiring to the rear lights. I have seen these older Toyota vehicles rear lighting short out on the lights themselves due to the way the light circuit was made on the lamp housing. Look at the housing circuit on the light to see if one is touching another, and that could tell you why it is malfunctioning. There could also be a problem with the brake light switch. If you are not comfortable dealing with wires, I recommend getting in touch with a certified mechanic who can look at your brake light issue for you to see what’s going on.

EPC light on 2004 Jetta. Code said brake switch faulty, but brakes lights worked. Replaced brake switch, now no brake lights.
ANSWER : Hi there. The first thing that pops in my mind beyond of what you have listed is perhaps the electrical harness attached to the brake switch. Perhaps the harness itself is damaged or you have an exposed wire, loose ground wire somewhere. You might want to have a professional mobile mechanic come to your location and complete a brake lights not working inspection to help you diagnose this issue.

Brake sensor is to sensitive causing brakes to flicker while driving. 2005 Mercury Montego
ANSWER : Hi there – your brake light switch needs a minor adjustment. It is adjusted too "tight" or close to the brake pedal lever, or possibly has failed. Adjusting/replacing it will eliminate this flickering problem. I recommend a brake light isn’t working inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

Brake lights are not working. replaced brake light swtch still no brake lights. the third brake light the connection was melted at
ANSWER : The first thing to do is to repair third brake light and replace the brake light fuse and then see if the third brake lights work and the lower lights start working? If only the 3rd brake light starts working then you may need a further checks on the turn signal flasher or switch could be bad.

No dash lights, back right tail light is out, no parking lights. Brake lights work though as does head lights.
ANSWER : Hi there. In many cases, when you have electrical problems like you’re describing, it’s caused by multiple electrical component failure. It’s likely that a few electrical relays are not working; especially if you have systems that utilize the same components (such as your brake light and tail lights). I would recommend having a professional mobile mechanic come to your location to complete an electrical problems inspection first, so they can pinpoint what is damaged and recommend the right repairs.

Dashboard warning lights come on during acceleration
ANSWER : Hello. Thanks for writing in about your Infiniti EX35. It sounds like one of your sensors for the system is reading incorrectly. I usually check the tires first as an odd tire on the car will cause this. If the tires are fine, then a scan tool would need to be used to see what the other sensors are reading. Most of the time, it is caused by the yaw sensor or the steering angle sensor. If you want to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to determine the cause of the Warning Lights and let you know what needs repair.

My brake lights and dash brake light come on while driving.
ANSWER : These types of warning lights will generally store a fault code in one or more of the vehicles control modules. The warning lights you are getting may be the result of a faulted brake pedal position sensor or wheel speed sensors. Further diagnosis will be necessary to determine the exact cause. Consider hiring an experienced technician like one from YourMechanic who can come out for a closer look and offer a more personal diagnosis of your warning lights.

Brake warning light comes on intermittently when I accelerate or drive uphill
ANSWER : Check the brake fluid level. If the level is low, it will illuminate the "Brake" light. Many time as the brake linings wears, the level of fluids will drop to keep the pads close to the rotor. If the fluid is low, the brake linings and the brake hydraulic system should be checked for leaks. You may want to enlist the help of a mechanic, such as one from YourMechanic, to inspect and recommend repairs to the brake system.