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Brake Pedal Excessive Travel

WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.
Step Action Yes No
DEFINITION: Brake pedal travels further than expected to obtain firm pedal and/or firm pedal cannot be obtained, pedal fades away, or pedal is spongy.
1 Were you sent here from the Hydraulic Brake Symptom table? Go to Step 2  -
2 Inspect the travel and feel of brake pedal applies. Perform the following:
  1. Apply the brake pedal several times to fully deplete the power reserve.
  2. With power reserve depleted, apply the brake pedal with light, steady pressure and hold for 15 seconds. Observe pedal travel and feel.
  3. Apply the brake pedal with light, steady pressure, then without pumping the pedal, reduce pressure and reapply pressure several times. Observe pedal travel and feel for each apply.
  4. Apply the brake pedal slowly, then release and apply the pedal quickly. Observe pedal travel and feel for each apply.

Did you complete the brake pedal travel and feel inspections?		 Go to Step 3  -
3
  1. Inspect the hydraulic brake system for the conditions listed, based on the following symptoms observed during the pedal travel and feel inspections.
    • Pedal feel was spongy.
      • Air in hydraulic system
      • External brake fluid leaks
      • Soft, weak or damaged hydraulic hoses; expanding under pressure
    • Pedal fell away and/or traveled to or almost to floor.
      • External brake fluid leaks
      • Poor brake fluid quality; low boiling point
      • Internal brake fluid leaks; improperly functioning master cylinder
    • Pedal was somewhat firm then dropped slightly, or pedal rose with successive applies, or pedal travel was different between slow and quick applies.
      • Internal brake fluid leaks; improperly functioning master cylinder
      • Poor brake fluid quality; low boiling point
      • Binding wheel cylinder pistons, if equipped
    • Pedal returned to rest slowly after any of the applies.
      • Internally damaged flexible brake hoses; hindering fluid return
      • Binding caliper pistons
      • Binding wheel cylinder pistons, if equipped
      • Internal brake fluid leaks; improperly functioning master cylinder
  2. Repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis .
  3. Re-inspect brake pedal apply travel and feel.
Did you find and correct a condition?		 Go to Step 8  Go to Step 4 
4
  1. Inspect the disc brake system for the following conditions:
    • Cracked, excessively worn or damaged linings
    • Cracked, excessively worn or damaged rotors
    • Improperly operating, binding or damaged caliper hardware and/or lining hardware
    • Loose or missing caliper hardware and/or lining hardware
    • Excessive assembled lateral runout (LRO) of rotor friction surfaces
    • Bent or damaged caliper or mounting component
  2. Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis .
  3. Re-inspect brake pedal apply travel and feel.
Did you find and correct a condition?		 Go to Step 8  Go to Step 5 
5 Inspect for proper brake pedal travel.
Is the brake pedal travel distance within the acceptable limits?		 Go to Step 7  Go to Step 6 
6
  1. Inspect for worn, missing, misaligned, bent or damaged brake pedal system components.
    • For the brake pedal pushrod component inspection, refer to Brake Pedal Pushrod Inspection .
    • Inspect the brake pedal bushings for binding, excessive wear and/or damage and inspect the brake pedal for a misaligned, bent, and/or damaged condition.
  2. Replace the brake pedal system components that are worn, missing, misaligned, bent or damaged.
Did you find and replace any worn, missing, misaligned, bent or damaged brake pedal system components?		 Go to Step 8  Go to Step 7 
7
  1. Inspect the brake assist system for the following conditions:
    • Vacuum leaks and/or improperly operating check valve, if equipped with vacuum assist
    • Power steering fluid leaks, if equipped with hydraulic power assist
    • Damaged or improperly operating brake booster assembly
  2. Adjust, repair or replace components as necessary. Refer to Brake Assist System Diagnosis .
Did you find and correct a condition?		 Go to Step 8  -
8
  1. Install or connect components that were removed or disconnected during diagnosis.
  2. Road test the vehicle in order to confirm proper operation. Refer to Brake System Vehicle Road Test .
Is the condition still present?		 Go to Step 2  System OK
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