Brake System
In this manual: Brake System
~5min read
4special tools
Specifications
Specifications
| Item | Specification | |
| Master Cylinder | Type | Single |
| Cylinder Inner Diameter | Ø 20.64 mm (0.8125 in.) | |
| Piston Stroke | 36 ± 1 mm (1.4173 ± 0.0393 in.) | |
| Fluid Level Sensor | Provided | |
| Brake booster | Type | 10-inch Single |
| Booster Ratio | 8 : 1 | |
| Front Disc Brake (14 in.) | ||
| Type | Ventilated Disc | |
| Rear Disc | 256 mm (10.0787 in.) | |
| Disc thickness | 22 mm (0.8661 in.) | |
| Disc Service Limit |
20.4 mm (0.8031 in.) | |
| Cylinder Type | Single piston | |
| Front Disc Brake (15 inch) | ||
| Type | Ventilated Disc | |
| Rear Disc | 280 mm (11.0236 in.) | |
| Disc Thickness | 22 mm (0.8661 in.) | |
| Disc Service Limit | 20.4 mm (0.8031 in.) | |
| Cylinder Type | Single piston | |
| Rear Disc Brake | ||
| Type | Solid Disc | |
| Disc O.D. | 262 mm (10.3149 in.) | |
| Disc thickness | 10.0 mm (0.3937 in.) | |
| Disc Service Limit | 8.4 mm (0.3307 in.) | |
| Cylinder Type | Single piston | |
| Drum Brake | ||
| Type | Leading Trailing | |
| Drum (Disc) ID | Ø 203 mm (7.9921 in.) | |
| Lining Thickness | 3.9–4.5 mm (0.1535–0.1772 in.) | |
Specifications (ABS)
| Part | Item | Standard Value | NOTE |
| HECU | System | 4-Channel 4-Sensor (Solenoid) | |
| Type | Motor, Integrated Valve Relay Type | ||
| Operating Voltage | 10 - 16 V | ||
| Operating Temperature | -40 to 120 °C | ||
| Engine Power | 230 W | ||
| Active Wheel Speed Sensor (ABS) | Supply Voltage | 4.5–20 V DC | |
| Low Output Current | 5.9–8.4 mA | ||
| High Output Current | 11.8–16.8 mA | ||
| Output range | 1 - 2500 Hz | ||
| Tone wheel | 48 teeth | ||
| Air gap | 0.4 – 1.5 mm |
Specifications (ESC)
| Part | Item | Standard Value | NOTE |
| HECU | System | 4-Channel 4-Sensor (Solenoid) | Full Control |
| Type | Motor, Integrated Valve Relay Type | (ABS, TCS, VSM, ESC) | |
| Operating Voltage | 10 - 16 V | ||
| Operating Temperature | -40 to 120 °C | ||
| Engine Power | 270 W | ||
| Active wheel speed sensor | Supply Voltage | 4.5–20 V DC | |
| Low Output Current | 5.9–8.4 mA | ||
| High Output Current | 11.8-16.8 mA | ||
| Output range | 1 - 2500 Hz | ||
| Tone wheel | 48 teeth | ||
| Air gap | 0.4 – 1.5 mm |
Service Standard
| Items | Standard Value |
| Brake pedal height | 180.8 mm (7.1181 in.) |
| Brake pedal full travel | 108 mm (4.2519 in.) |
| Stop Lamp Switch Clearance | 1.0–2.0 mm (0.04–0.08 in.) |
| Front Brake Pad Thickness (14, 15 in.) | 11 mm (0.4331 in.) |
| Front Brake Pad Wear Limit (14, 15 in.) | 2 mm (0.0787 in.) |
| Rear brake pad thickness | 10 mm (0.3937 in.) |
| Rear brake pad wear limit | 2 mm (0.0787 in.) |
Tightening torque
| Items | N·m | kgf·m | lbf·ft | |
| Master Cylinder to Brake Booster Nut | 9,8 - 15,7 | 1,0 - 1,6 | 7,2 - 11,6 | |
| Brake Tube Flare Nuts at Master Cylinder | ABS | 13,7 - 16,7 | 1,4 - 1,7 | 10,1 - 12,3 |
| ESC | 18,6 - 22,6 | 1,9 - 2,3 | 13,7 - 16,6 | |
| Front caliper guide rod bolts | 21,6 - 31,4 | 2,2 - 3,2 | 15,9 - 23,1 | |
| Rear caliper guide rod bolts | 21,6 - 31,4 | 2,2 - 3,2 | 15,9 - 23,1 | |
| Front caliper assembly to steering knuckle | 78,5 - 98,1 | 8,0 - 10,0 | 57,9 - 72,3 | |
| Rear caliper assembly to steering knuckle | 78,5 - 98,1 | 8,0 - 10,0 | 57,9 - 72,3 | |
| Brake pedal bracket bolts | 16,7 - 25,5 | 1,7 - 2,6 | 12,3 - 18,8 | |
| Wheel speed sensor mounting bolt | 7,8 - 11,8 | 0,8 - 1,2 | 5,8 - 8,7 | |
| HECU Bracket Mounting Bolts | 16,7 - 25,5 | 1,7 - 2,6 | 12,3 - 18,8 | |
| HECU Brake Tube Flare Nuts | 13,7 - 16,7 | 1,4 - 1,7 | 10,1 - 12,3 | |
Lubricants
| Items | Recommended | Quantity |
| Brake fluid | DOT 3 or DOT 4 | As required |
| Brake pedal bushing and bolt | Chassis grease | As required |
| Parking brake shoe and backing plate contact surface | Heat-resistant grease | As required |
Special Service Tools
Special Service Tools
| Use | ||
| 09581-11000 Piston Expander |
 |
Front Disc Brake Piston Compression |
| 09580 - 0U000 Brake Piston Adjuster |
 |
"Removal and Installation of Rear Disc Brake Piston". |
| SCC reflector 09964-C1100 |
 |
SCC Radar Alignment Reflector |
| Calibration beam 09964-C1200 |
 |
Laser for determining vehicle center. |
| Stand 09964-C1300 |
 |
SCC reflector or vertical/horizontal laser support. |
| Sensor Cover Installer 09527-1C010 |
 |
Used to install the wheel speed sensor cover (Sensor cover: Φ58.4) |
Troubleshooting
Troubleshooting
Symptom Table
Use the table below to find the cause of the problem. The numbers indicate the priority of the likely cause.
Check each part in order.
If necessary, replace these parts.
| Symptom | Possible Cause | Countermeasure |
| Low or Spongy Pedal | Brake System (Fluid Leak) | Repair |
| Brake System (Air Intrusion) | Bleeding Procedure | |
| Piston Seal (Worn or Damaged) | Replace | |
| Rear Brake Shoe Clearance (Incorrect Adjustment) | Adjust | |
| Master Cylinder (Malfunction) | Replace | |
| Brake Drag | Brake Pedal Free Travel (Minimum) | Adjust |
| Parking Brake Cable Length (Adjustment Problem) | Adjust | |
| Parking Brake Cable (Seized) | Repair | |
| Rear Brake Shoe Clearance (Adjustment Problem) | Adjust | |
| Lining and Backing Plate (Twisted or Cracked) | Replace | |
| Piston (Trapped) | Replace | |
| Piston (Seized) | Replace | |
| Anchor or Return Spring (Malfunction) | Replace | |
| Brake Booster (Vacuum Leak) | Repair | |
| Master Cylinder (Malfunction) | Replace | |
| Uneven Braking | Piston (Trapped) | Replace |
| Lining and Backing Plate (Oil Stains, Cracks or Warpage) | Replace | |
| Heavy Pedal Effort and Brake Problems | Brake System (Fluid Leak, Air Intrusion) | Perform the Bleeding Procedure |
| Brake Shoe or Lining (Worn) | Replace | |
| Pad Shim or Backing Plate (Cracked or Twisted) | Replace | |
| Rear Brake Shoe Clearance (Adjustment Problem) | Adjust | |
| Pad Shim or Backing Plate (Oil Stain) | Replace | |
| Pad Shim or Backing Plate (Slippery) | Replace | |
| Disc (Scored) | Replace | |
| Brake Booster (Vacuum Leak) | Repair | |
| Brake noise | Pad Shim or Backing Plate (Cracked or Twisted) | Replace |
| Loose Wheel Bolt and Caliper | Adjust | |
| Pad Sliding Problems (Uneven Pad Wear) | Replace | |
| Lining or Backing Plate (Dirty) | Cleaning | |
| Pad Shim or Backing Plate (Slippery) | Brake Pad Replacement | |
| Anchor or Return Spring (Malfunction) | Replace | |
| Brake Pad Shim (Damaged) | Replace | |
| Retaining Spring (Damaged) | Replace | |
| Foreign Object Caught Between Disc and Pad | Cleaning | |
| Corrosion on Disc | Brake Road Test and Cleaning * Remove friction corrosion by performing a brake road test |
|
| Cave-in Disc | Replace | |
| Brakes Not Fully Effective (at high driving speed) |
Brake Shoe or Lining (Worn) | Replace |
| Master Cylinder (Malfunction) | Replace | |
| Brake Vibration | Brake Booster (Vacuum Leak) | Repair |
| Pedal Free Separation | Adjust | |
| Master Cylinder (Malfunction) | Replace | |
| Master Cylinder Cap Damaged | Replace | |
| Brake Line Damaged | Replace | |
| Caliper Return Problem (while wheel rotates, check for noise) | Replace | |
| Converted Disc | Replace |
Test yourself
A quick Kia Rio YB quiz: every answer comes with an explanation and a link to the manual page.
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