Hyundai Sonata: Troubleshooting - General Information - Brake SystemHyundai Sonata: Troubleshooting

Troubleshooting
Problem Symptoms Table
Use the table below to help you find the cause of the problem. The numbers indicate the priority of the like cause of the problem. Check each part in order.
If necessary, replace these parts.
Symptom
Suspect Area
Reference
Lower pedal or
spongy pedal
1. Brake system (Fluid leaks)
2. Brake system (Air in)
3. Piston seals (Worn or damaged)
4. Rear brake shoe clearance(Out of adjustment)
5. Master cylinder (Inoperative)
repair
air·bleed
replace
adjust
replace
Brake drag
1. Brake pedal free play (Minimum)
2. Parking brake lever travel (Out of adjustment)
3. Parking brake wire (Sticking)
4. Rear brake shoe clearance(Out of adjustment)
5. Pad or lining (Cracked or distorted)
6. Piston (Stuck)
7. Piston (Frozen)
8. Anchor or shoe (Inoperative)
9. Booster system (Vacuum leaks)
10. Master cylinder (Inoperative)
adjust
adjust
repair
adjust
replace
replace
replace
replace
repair
replace
Brake pull
1. Piston (Sticking)
2. Pad or lining (Oily)
3. Piston (Frozen)
4. Disc (Scored)
5. Pad or lining (Cracked or distorted)
replace
replace
replace
replace
replace
Hard pedal but
brake inefficient
1. Brake system (Fluid leaks)
2. Brake system (Air in)
3. Pad or lining (Worn)
4. Pad or lining (Cracked or distorted)
5. Rear brake shoe clearance(Out of adjustment)
6. Pad or lining (Oily)
7. Pad or lining (Glazed)
8. Disc (Scored)
9. Booster system (Vacuum leaks)
repair
air·bleed
replace
replace
adjust
adjust
replace
replace
repair
Noise from brake
1. Pad or lining (Cracked or distorted)
2. Installation bolt (Loosen)
3. Disc (Scored)
4. Sliding pin (Worn)
5. Pad or lining (Dirty)
6. Pad or lining (Glazed)
7. Anchor or shoe (Faulty)
8. Brake pad shim (Damage)
9. Shoe hold-down spring (Damage)
replace
adjust
replace
replace
clean
replace
replace
replace
replace
Brake fades
1. Master cylinder (Inoperative)
replace
Brake vibration,
pulsation
1. Brake booster (Vacuum leaks)
2. Pedal free play
3. Master cylinder (Inoperative)
4. Caliper (Damage)
5. Master cylinder cap seal
6. Damaged brake lines
replace
adjust
replace
replace
replace
replace
Brake Chatter
Brake chatter is usually caused by loose or worn components, or glazed or burnt linings. Rotors with hard spots can also contribute to brake chatter. Additional causes of chatter are out-of-tolerance rotors, brake lining not securely attached to the shoes, loose wheel bearings and contaminated brake lining.


    Special Service Tools
    Special Service Tools Tool(Number and Name)IllustrationUse09581-11000Piston expanderSpreading the rear disc brake piston.09580 - 0U000Brake piston adjusterRemoval and installation of the rear di ...

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