Troubleshooting - Brakes

Introduction

This troubleshooting guide is intented to help identify and repair problems with the brake system. The following is a list of problem symptoms discussed in this guide:

• Brake Pedal Goes to Floor When Depressed

• Brake Pedal Spongy When Depressed

• High Pitched Squeal During Braking

• High Pitched Squeal During Driving - Goes Away During Braking

• Vehicle Pulls to One Side During Braking

• Pulsations or Jerky Braking

Brake Pedal Goes to Floor When Depressed Possible Causes Checks Procedure Brake fluid is low. Check brake reservoir level and fill if necessary. N/A Brake Master Cylinder bad. Check for signs of leakage from Master Cylinder in the engine compartment next to the firewall and inside the driver’s footwell. If there are signs of leakage or other causes have been eliminated, replace the Master Cylinder. BRAKE-06 Air in the brake system. Bleed brakes. BRAKE-01 Brake Pedal Feels Spongy During Braking Possible Causes Checks Procedure Master Cylinder Mounting bolts loose. Check bolts and tighten if necessary. N/A Brake Master Cylinder bad. Check for signs of leakage from Master Cylinder in the engine compartment next to the firewall and inside the driver’s footwell. If there are signs of leakage or other causes have been eliminated, replace the Master Cylinder. BRAKE-06 Air in the brake system. Bleed brakes. BRAKE-01 High Pitched Squeal During Braking Possible Causes Checks Procedure Brake pads worn. Replace brake pads immediately. BRAKE-02 High Pitched Squeal During Driving - Goes Away During Braking Possible Causes Checks Procedure Excessive Brake Dust. Brake dust which gets between the back of the brake pad and the caliper piston can cause vibration (squealing) during driving. When the brake pedal is depressed, the piston presses against the brake pad and stops the vibration (and the squealing). There are a number of methods which can be utilized to stop vibration: Anti-Squeal Pads. Most brakes pad sets now days come with anti-squeal pad. However, if yours do not have them, they can usually be obtained at most auto parts stores. Brake Pad Grease. Applying brake pad grease to the back of the brake pad can stop vibration. The grease is sold in packets at most auto parts stores. However, bearing grease works just as well. Adhesive. When other methods don’t seem to work, I have stopped brake squeal by applying some adhesive to the back of the brake pad. This adheres the pad to the caliper piston and will normally stop the vibration. A number of adhesives will work but, I normally use 3M Vinyl and Trim Adhesive. Brake Pads. Some brake pads produce significantly more dust than others. You may try swapping to a pad that produces less brake dust. BRAKE-02 Vehicle Pulls to One Side During Braking Possible Causes Checks Procedure Wrong Tire Pressure. Check that all tires have the correct tire pressure. N/A Suspension Out of Alignment. Have alignment checked and corrected if necessary. N/A Crimped or Pinched Brake Line. Inspect all brake lines. N/A Loose or Malfunctioning Brake Caliper. Raise wheels off ground, apply brakes, and attempt to turn wheels by hand. If any wheels brake caliper is not working, attempt to bleed brake for that wheel to see if brake line is clogged. If the brake line is not clogged the caliper is probably bad and needs to be replaced or rebuilt. N/A Pulsations or Jerky Braking Possible Causes Checks Procedure Brake rotor lateral runout bad. Check rotor lateral runout within specs. BRAKE-04 Brake pads contaminated. If the brake pads are contaminated with brake fluid or oil, it can cause jerky brake operation. Remove the brake pads, check, and replace if necessary. BRAKE-02