Brake system fault diagnostics [Toyota RAV4 XA20]

Note: Before you conclude that the problem is related to the brake system, make sure of the following:

• The tires are in good condition and properly inflated.
• The front wheel alignment angles are adjusted correctly.
• The placement of the load does not cause uneven subsidence of the vehicle.

The car pulls to the side when braking

• The tires are incorrectly inflated ("Weekly checks").
• The front wheel alignment angles are out of adjustment (needs to be adjusted).
• Tires of different sizes are mounted on one axle.
• Brake lines or hoses are pinched (chapter 9).
• The brake mechanisms of the wheels are faulty (chapter 9).
• The suspension parts have become loose (chapter 10).
• The brake caliper mounts are loose (chapter 9).
• Excessive wear of the brake friction linings on one side.

Noise (grinding or squealing) when braking

• Excessive wear of front and/or rear disc brake pads (chapter 9).

Brake pedal pulsation (uneven braking)

• Brake disc warping (beating) (chapter 9).
• Uneven wear of brake pads (chapter 9).
• Disc material defect (chapter 9).

Excessive force on the brake pedal is required to stop the car

• The brake booster is faulty (chapter 9).
• Malfunction in the brake circuit separation system (chapter 9).
• Excessive wear of brake pads (chapter 9).
• The piston is stuck in the brake mechanism working cylinder (chapter 9).
• The brake pads are dirty or oily (chapter 9).
• The working surface of the brake discs has grooves and/or "glaze" (chapter 1A or 1B).
• The new pads have not been worn in. It will take some time for the pads to become accustomed to the drums or discs.
• The vacuum pump is faulty (models with diesel engine) (chapter 9).

Excessive brake pedal travel

• Malfunction in the brake circuit separation system (chapter 9).
• Not enough fluid in the master cylinder (chapters 1A or 1B and 9).
• Air in the hydraulic drive system (chapters 1A or 1B and 9).

Wheel braking

• The mobility of the pistons in the main brake cylinder is impaired (chapter 9).
• Brake lines or hoses are pinched (chapters 1A or 1B and 9).
• The parking brake adjustment is incorrect (chapter 9).
• The working brake cylinder of one of the mechanisms is jammed (chapter 9).

Jerking when braking

• Pressure regulator valve malfunction (chapter 9).
• Brake booster malfunction (chapter 9).
• Jamming in the brake pedal mechanism (chapter 9).

"Soft" brake pedal

• Air in the hydraulic system (chapter 9).
• The brake master cylinder mounting bolts have become loose (chapter 9).
• The brake master cylinder is faulty (chapter 9).

The brake pedal, when pressed, gradually "goes to the floor"

• The fluid level in the reserve tank is insufficient, caused by a leak from the working cylinder or damage in the hydraulic pipes or their connections (chapter 9).
• The brake master cylinder is faulty (chapter 9).
• Loose connections, damaged or disconnected brake lines (chapter 9).

The parking brake does not hold the car on a slope

• The parking brake drive adjustment is disturbed (chapter 9).