Hard Brake Pedal Diagnosis - Ford Mustang 2020
A consistently hard brake pedal indicates a loss of power brake assist, likely due to a vacuum leak, failed brake booster, or faulty check valve. This significantly increases stopping distance and effort.
Diagnosis Details
Possible Causes
Brake booster vacuum hose leak or check valve failure
Failed brake booster diaphragm
Vacuum pump issue (if equipped) or engine vacuum problem
Related OBD-II Codes
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What You Should Do
Inspect the vacuum hose from the intake manifold to the brake booster for cracks, disconnection, or collapse.
Check the one-way check valve at the booster for proper operation.
If no leaks are found, test the brake booster for internal failure.
Do not drive the vehicle until the issue is resolved.
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Disclaimer: This AI-generated diagnosis is for informational reference only. Always consult a qualified mechanic for an in-person inspection. AutOwner is not responsible for decisions made based on this information.