Diagnostics of brake hydraulic system faults (Renault Clio 1)

Note: Before troubleshooting the brake system, make sure the tires are in good condition and properly inflated, that the front wheel alignment is correct, and that the vehicle load is distributed correctly. In case of any malfunctions in the anti-lock braking system, it is permissible to check the condition of all pipe and hose joints; in other cases, you should contact a Renault dealer for diagnostics.

The car pulls to the side when braking

• The front and/or rear brake pads on the corresponding side are worn or dirty (Sections 1 and 9).
• The front or rear brake caliper piston is stuck (Section 9).
• Brake pads with different lining materials are installed on different sides (Section 9).
• The rear brake caliper or backing plate mounting bolts are loose (Section 9).
• Worn or damaged steering or suspension components (Sections 1 and 10).

Noise (or squealing) when braking

• The brake lining friction material is worn down to the metal base (Sections 1 and 9).
• Brake disc corrosion - may appear after a long period of parking of the car (Sections 1 and 9).

Excessive brake pedal travel

• The rear drum brake self-adjusting adjuster is faulty (Section 9).
• The master cylinder is faulty (Section 9).
• Air in the brake system (Section 9).
• The vacuum booster unit is faulty (Section 9).
• Vacuum pump faulty - diesel models (Section 9).

The brake pedal springs when pressed

• Air in the brake hydraulic system (Section 9).
• Damaged rubber brake hoses (Sections 1 and 9).
• The master cylinder fasteners are loose (Section 9).
• The master cylinder is faulty (Section 9).

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

• The vacuum booster unit is faulty (Section 9).
• The brake booster vacuum hose is disconnected, damaged, or leaking (Sections 1 and 9).
• Vacuum pump faulty - diesel models (Section 9).
• One of the circuits of the brake hydraulic system is damaged (Section 9).
• The brake caliper piston or the brake wheel cylinder is jammed (Section 9).
• Brake pads are incorrectly adjusted or installed (Section 9).
• Incorrect brake pads installed (Section 9).
• The brake pads are oily (Section 9).

When braking, intense vibration is felt in the brake pedal or steering wheel

• Severe wear or deformation of the brake disc (Section 9).
• Worn brake pads (Sections 1 and 9).
• The brake caliper or rear brake shield mounting bolts are loose (Section 9).
• Worn suspension or steering components or their mountings (Sections 1 and 10).

The pedal pulsates when braking hard

• Normal feature of the ABS system - no malfunction.

Wheel braking

• The brake caliper piston or the piston of the brake master cylinder is jammed (Section 9).
• The handbrake mechanism or linkage is not adjusted correctly (Section 9).
• The master cylinder is faulty (Section 9).

Rear wheel lockup during normal braking

• The brake caliper piston or the piston of the brake master cylinder is jammed (Section 9).
• The brake pressure regulator is faulty (Section 9).