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On modern vehicles the brake system is enhanced by a vacuum operated "booster". This makes the brake pedal softer and more responsive. When the engine is turned off the engine no longer produces vacuum to supply the booster so the pedal gets hard.
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∙ 14y ago
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What are symptoms of a bad power brake booster?
hard brake pedal is the most obvious sign only way i know to test a booster, is to turn engine off. use brakes several times till pedal is hard. then with brake applied,start engine. the brake pedal should then soften.if the pedal stays hard the booster is bad
How do you check a hydraulic brake servo?
With the engine off, press hard on the brake pedal. Turn the engine on and the pedal should depress slightly but no more than an inch or two. If your brakes either drag or stick on, or sometimes the pedal goes real hard under foot it means your servo is shot!
What does it mean when you depress brake pedal your lights go dim each time?
depress the brake pedal and turn the engine switch to the start posiiton and start the engine,,, Does this mean to hold the brake down until you hear the engine start.
What can I do if i can not remove my keys from my 2004 Volvo S40?
Our car is S40 with automatic transmission. Put car in "park". Start engine. Put foot hard down on brake pedal. Turn engine off with the brake still hard on. In our car, the key came out easily.
When you turn off the engine of a 1994 Cutlass Ciera why would the tail-lights remain on?
Check the brake light switch, it's under the dashboard, connected to the brake pedal.
Where is a brake light switch on a Nissan?
The brake light switch on a Nissan is located just behind the brake pedal. It sends a signal to the brake lights when the pedal is pressed to turn them on.
Brake lights will not turn of in vectra?
the switch on brake pedal is faulty and needs replacing
My daughter has a 1999 Ford Escort ZX2 she has to push down on the brake pedal very hard to get the car out of park and into gear?
If you turn the engine off the gearshift will move easily. Its the brake light switch. It's a multi-switch that also operates the gearshift lock solenoid.
How do you get tail lights to turn off when the car engine and lights are off?
Look up under your dash where the brake pedal is attached, you will see a switch that makes the brake lights turn on when you step on the pedal and off when you leave off the pedal. The switch is probably stuck. In the meantime you could disconnect the negative battery cable so your battery doesn't die.
What does it mean when brake lights won't turn off when the truck is off or running?
Take your toe and pick UP on the brake pedal. The brake pedal may not be returning as it should.
What is cause the the rear lights still on after turn off engine?
If you mean the brake lights are staying on, then the switch at thte pedal is sticking. Could be dirty or need adjusted. Switch is under dash at the pedal.
What would cause the brake pedal to be hard and not go to the floor and still engage the brakes?
You could have a clogged brake line, most likely one of the front rubber ones. The Brake booster might not be working correctly. Run the engine for a few moments, then turn the key off. Once the engine dies, press the brake pedal a few times. You should hear a hissing noise each time you press the pedal. Then hold the pedal down and start the engine. The pedal should move and get softer. If none of this occurs, verify that the booster has a vacuum source. If the booster has a vacuum source, and still does not boost the pedal effort, the booster is more than likely bad. One other alternative would be a bad check valve. Simply remove the valve and blow into it. It should blow easily in one direction, and not at all in the other.
