my Toyota Corolla E170 (2013-2019) has a hard brake pedal, what could be wrong

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is on a flat surface and secure with wheel chocks.
• Disconnect the negative battery terminal to prevent electrical issues.

2. Inspect and Refill Brake Fluid

• Open the master cylinder reservoir cap.
• Check the brake fluid level; if low, top off with the specified brake fluid (DOT 3 or DOT 4 as per manufacturer).
• Replace the cap securely.

3. Evaluate and Replace Brake Booster

• Tools Required: Wrench set, vacuum gauge, screwdriver set.
• Disconnect the vacuum line from the brake booster.
• Unbolt the brake booster from the firewall (usually 4-5 bolts).
• Remove the pushrod from the brake pedal assembly.
• Replace with a new brake booster if it is faulty (check for proper operation as per diagnostic steps).

4. Inspect and Repair Vacuum Lines

• Follow the vacuum lines from the engine to the brake booster.
• Look for any signs of wear, cracks, or disconnections.
• Replace any damaged vacuum lines with new ones.

5. Reassemble and Test

• Reconnect the vacuum line to the brake booster.
• Reconnect the negative battery terminal.
• Test the brake pedal to ensure it feels normal and not hard.