Brake pedal won't depress and car won't start

Symptoms

• Brake pedal feels rock hard or won't move at all
• Push-button start won't respond without the brake pressed
• Shifter may also refuse to move out of Park
• May have happened suddenly or developed gradually

Likely causes

• CommonBrake booster vacuum issue making the pedal very hardA failed brake booster can make the pedal feel extremely stiff, sometimes seeming stuck.
• PossibleFrozen brake pedal linkage in very cold weatherIce or extreme cold can stiffen linkages temporarily.
• PossibleShift interlock solenoid malfunction (separate from the pedal itself)This can prevent the car from recognizing the brake is pressed even if it physically moves.
• PossibleObject lodged under the brake pedalFloor mats or debris can physically block pedal travel.
• Less commonBrake system hydraulic lockup (rare, serious)A serious hydraulic fault can make the pedal unmovable and affects actual braking, not just starting.

What to do

1. Check under and around the brake pedal for a stuck floor mat, object, or debris blocking its travel.
2. If the pedal is simply very stiff rather than completely immovable, this may point to a brake booster vacuum issue rather than a true blockage.
3. In very cold weather, allow the car to sit and warm slightly, since ice can occasionally stiffen linkages temporarily.
4. Do not force the pedal aggressively if it feels seized, since this could indicate a real brake system problem.
5. If the pedal frees up and the car starts, still get the brakes inspected soon, since a stiff pedal can indicate a real underlying issue.
6. If the pedal won't move at all and nothing is blocking it, do not attempt to drive the vehicle even if you can get it to start.
7. Have the vehicle towed if the brake pedal is truly stuck, since this affects your ability to stop safely, not just start the car.
8. Have a mechanic inspect the brake booster, master cylinder, and pedal linkage before returning the car to service.

When to call a pro

Any brake pedal problem affecting your ability to stop safely should be diagnosed and repaired by a qualified mechanic before the car is driven again.

Safety