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Hydraulic Brake System Chevrolet Corvette C6

Mechanical - Hydraulic 9 illustrations ~10181 words

Fastener Tightening Specifications

ApplicationSpecification
MetricEnglish
Brake Hose Bracket Bolt10 N.m89 lb in
Brake Hose Fitting Bolt40 N.m30 lb ft
Brake Pedal Pivot Nut29 N.m21 lb ft
Brake Pipe Fitting18 N.m13 lb ft
Master Cylinder Brake Pipe Fitting24 N.m18 lb ft
Master Cylinder Nut18 N.m13 lb ft
Power Vacuum Brake Booster Nut27 N.m20 lb ft

Brake Component Specifications

ApplicationSpecification
MetricEnglish
Brake Caliper Bleeder Valve (Front)12 N.m106 lb in
Brake Caliper Bleeder Valve (Rear)12 N.m106 lb in

Brake Component Specifications

Brake System Specifications

ApplicationSpecification
MetricEnglish
Brake Pedal Travel Maximum specification with 310 N (70 lbs) of force applied to the brake pedal with the ignition OFF and the booster power reserve depleted74 mm2.91 in

Scheme 1

Scheme 1: Hydraulic Brake Schematics
Scheme 1: Hydraulic Brake Schematics

DIAGNOSTIC CODE INDEX

DTCDescription
DTC C0267C0267 00: Low Brake Fluid Indicated

DIAGNOSTIC CODE INDEX

Diagnostic Starting Point - Hydraulic Brakes

Begin the system diagnosis with Diagnostic System Check - Vehicle . The Diagnostic System Check - Vehicle will provide the following information

  1. The identification of the control modules which command the system
  2. The ability of the control modules to communicate through the serial data circuit
  3. The identification of any stored diagnostic trouble codes (DTCs) and their status

The use of the Diagnostic System Check - Vehicle will identify the correct procedure for diagnosing the system and where the procedure is located.

Diagnostic Instructions

  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/corvette/c6-2004-2014/remont/oem-general-information/#vehicle-diagnostic-information) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/corvette/c6-2004-2014/remont/oem-general-information/#vehicle-diagnostic-information__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/corvette/c6-2004-2014/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

Diagnostic Fault Information

CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Brake Fluid Level SignalC0267 0011
Park Brake Signal111
Ground1
1. Brake Warning Indicator Malfunction

Circuit/System Description

The brake fluid level switch monitors the level of brake fluid in the master cylinder. When the instrument panel cluster (IPC) sees the brake fluid level switch input grounded, it turns ON the Red Brake Warning indicator and sends a serial data message to the electronic brake control module (EBCM) that the brake fluid level is low.

Conditions for Running the DTC

Ignition ON.

Conditions for Setting the DTC

  1. Low brake fluid is detected.
  2. A short to ground exists on the signal circuit.

Action Taken When the DTC Sets

  1. The EBCM disables the antilock brake system (ABS)/traction control system (TCS) dynamic rear proportion (DRP) and vehicle stability enhancement system (VSES).
  2. A DIC message and/or a warning indicator may be displayed.

Conditions for Clearing the DTC

  1. The condition for the DTC is no longer present.
  2. The EBCM clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Reference Information

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/corvette/c6-2004-2014/remont/body-electrical/#wiring-systems-and-power-management-service-troubleshooting-diagnosis__circuit-testing)
  2. «Connector Repairs»(/chevrolet/corvette/c6-2004-2014/remont/body-electrical/#wiring-systems-and-power-management-service-troubleshooting-diagnosis__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/corvette/c6-2004-2014/remont/body-electrical/#wiring-systems-and-power-management-service-troubleshooting-diagnosis)
  4. «Wiring Repairs»(/chevrolet/corvette/c6-2004-2014/remont/body-electrical/#wiring-systems-and-power-management-service-troubleshooting-diagnosis__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Inspect for proper brake fluid level, the fluid level should be at or above the proper level. If low, refer to «Brake Fluid Loss»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-fluid-loss) .
  2. Ignition ON, observe the scan tool IPC Brake Fluid Level Switch parameter. The reading should be OFF.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the brake fluid level switch.
  2. Test for less than 1 ohm between the ground circuit terminal B and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool IPC Brake Fluid Level Switch parameter is OFF. If not the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the IPC.
  4. Install a 3A fused jumper wire between the signal circuit terminal A and ground. Verify the scan tool IPC Brake Fluid Level Switch parameter is ON. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the IPC.
  5. If all circuits test normal, test or replace the brake fluid level switch.

Component Testing

  1. Ignition OFF, disconnect the harness connector at the brake fluid level switch.
  2. Test for infinite resistance between the ground terminal B and the signal terminal A. If less than the specified value, replace the brake fluid level switch.

Repair Procedures

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Brake Fluid Level Indicator Switch Replacement»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system)
  2. «Control Module References»(/chevrolet/corvette/c6-2004-2014/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for EBCM or IPC replacement, setup, and programming

Symptoms - Hydraulic Brakes

IMPORTANTThe following steps must be completed before using the symptom tables.
  1. Perform «Diagnostic System Check - Vehicle»(/chevrolet/corvette/c6-2004-2014/remont/oem-general-information/#vehicle-diagnostic-information) before using the brake indicator symptom tables in order to verify that all of the following are true: There are no DTCs set. The control module(s) can communicate via the serial data link.
  2. Perform the «Brake System Vehicle Road Test»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) before using the hydraulic brake symptom tables in order to duplicate the customer's concern.
  3. Review the system operation in order to familiarize yourself with the system functions. Refer to the following: «Brake Warning System Description and Operation»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Hydraulic Brake System Description and Operation»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Brake Assist System Description and Operation»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Disc Brake System Description and Operation»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system)

Visual/Physical Inspection

  1. Inspect for aftermarket devices which could affect the operation of the brake warning system. Refer to «Checking Aftermarket Accessories»(/chevrolet/corvette/c6-2004-2014/remont/body-electrical/#wiring-systems-and-power-management-service-troubleshooting-diagnosis__checking-aftermarket-accessories) .
  2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

  1. «Brake Warning Indicator Malfunction»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system)
  2. «Brake Pulsation»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-pulsation)
  3. «Brake System Noise»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-system-noise)
  4. «Braking Action Uneven - Pulls to One Side»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system)
  5. «Braking Action Uneven - Front to Rear»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system)
  6. «Brake Pedal Excessive Travel»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-pedal-excessive-travel)
  7. «Brake Pedal Excessive Effort»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-pedal-excessive-effort)
  8. «Brakes Drag»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brakes-drag)
  9. «Brake System Slow Release»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-system-slow-release)
  10. «Brake Fluid Loss»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-fluid-loss)
  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/corvette/c6-2004-2014/remont/oem-general-information/#vehicle-diagnostic-information) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/corvette/c6-2004-2014/remont/oem-general-information/#vehicle-diagnostic-information__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/corvette/c6-2004-2014/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-procedure-instructions) provides an overview of each diagnostic category.
CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Brake Fluid Level SignalC0267 0011
Park Brake Signal111
Ground1
1. Brake Warning Indicator Malfunction

The instrument panel cluster (IPC) sees either the brake fluid level switch input grounded or the park brake switch input grounded and illuminates the Red Brake Warning indicator.

Schematic Reference

Connector End View Reference

Description and Operation

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/corvette/c6-2004-2014/remont/body-electrical/#wiring-systems-and-power-management-service-troubleshooting-diagnosis__circuit-testing)
  2. «Connector Repairs»(/chevrolet/corvette/c6-2004-2014/remont/body-electrical/#wiring-systems-and-power-management-service-troubleshooting-diagnosis__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/corvette/c6-2004-2014/remont/body-electrical/#wiring-systems-and-power-management-service-troubleshooting-diagnosis)
  4. «Wiring Repairs»(/chevrolet/corvette/c6-2004-2014/remont/body-electrical/#wiring-systems-and-power-management-service-troubleshooting-diagnosis__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

  1. Verify the park brake is released and the brake fluid is at or above the proper level. If low, refer to «Brake Fluid Loss»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-fluid-loss) .
  2. Command the IPC display test with a scan tool, the warning indicator should turn ON then OFF. If the red brake warning indicator does not illuminate, replace the IPC.
  3. Ignition ON, observe the scan tool IPC Park Brake Switch parameter while applying and releasing the park brake. The parameter should cycle between Applied and Released. If the parameter does not cycle between the specified values, refer to «Park Brake Switch Malfunction»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__park-brake-switch-malfunction) .
  4. Observe the scan tool IPC Brake Fluid Level Switch parameter. The reading should be OFF. If not the specified value, refer to «Brake Fluid Level Switch Malfunction»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-fluid-level-switch-malfunction) .

Park Brake Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the park brake switch.
  2. Ignition ON, verify the scan tool IPC Park Brake Switch parameter is Released. If not the specified value, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the IPC.
  3. Install a 3A fused jumper wire between the signal circuit terminal A and ground. Verify the scan tool IPC Park Brake Switch parameter is Applied. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance.
  4. If all circuits test normal, test or replace the park brake switch.

Brake Fluid Level Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the brake fluid level switch.
  2. Test for less than 1 ohm between the ground circuit terminal B and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool IPC Brake Fluid Level Switch parameter is OFF. If not the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the IPC.
  4. Install a 3A fused jumper wire between the signal circuit terminal A and ground. Verify the scan tool IPC Brake Fluid Level Switch parameter is ON. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the IPC.
  5. If all circuits test normal, test or replace the brake fluid level switch.
  1. Ignition OFF, disconnect the harness connector at the park brake switch.
  2. Test for infinite resistance between the signal terminal A and ground with the park brake released. If less than the specified value, replace the park brake switch.
  3. Test for less than 1 ohm between the signal terminal A and ground with the park brake applied. If greater than the specified range, replace the park brake switch.
  1. Ignition OFF, disconnect the harness connector at the brake fluid level switch.
  2. Test for infinite resistance between the ground terminal B and the signal terminal A. If less than the specified value, replace the brake fluid level switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. «Brake Fluid Level Indicator Switch Replacement»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system)
  2. «Parking Brake Indicator Switch Replacement»(/chevrolet/corvette/c6-2004-2014/remont/parking-brake-system/#parking-brake-system)
  3. «Control Module References»(/chevrolet/corvette/c6-2004-2014/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for IPC replacement, setup, and programming

Brake Pulsation

StepActionYesNo
DEFINITION: Fluctuation or pulsation is felt through the brake pedal, steering wheel, seat, floor, and/or in the vehicle ONLY when braking.
1Were you sent here from the Hydraulic Brake Symptom table?Go to Step 2Go to Diagnostic Starting Point - Hydraulic Brakes
2Inspect the disc brake system for the following conditions. Excessive thickness variation of rotor friction surfaces Excessive assembled lateral runout (LRO) of rotor friction surfaces Hard spots, heat checks, bluing discoloration of rotor friction surfaces; possibly due to brake drag Excessive corrosion of rotor friction surfaces; including red, gray or black oxidation Loose, damaged or missing caliper or lining hardware Bent or damaged caliper or mounting component Excessive LRO of wheel hub/axle flange; due to damage and/or loose or excessively worn bearings Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis . Did you find and correct a condition?Go to Step 3Go to Diagnostic Starting Point - Hydraulic Brakes
3Install or connect components that were removed or disconnected during diagnosis. 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 2System OK

Brake System Noise

StepActionYesNo
DEFINITION: Vehicle exhibits abnormal noise when braking; vehicle may exhibit abnormal noise during motion just after brake pedal release.
1Were you sent here from the Hydraulic Brake Symptom table?Go to Step 2Go to Diagnostic Starting Point - Hydraulic Brakes
2Inspect the disc brake system for the following conditions. Lining wear indicator contact with rotor Debris trapped between rotor and splash shield or backing plate; and/or debris trapped between rotor and linings Contaminated linings Aftermarket linings Glazed linings Distorted, cracked or damaged linings Excessively worn linings Damaged or excessively worn caliper hardware and/or lining hardware Incorrectly installed, loose or missing caliper hardware and/or lining hardware Lack of lubrication or excessive corrosion on metal to metal contact surfaces Bent or damaged splash shield or backing plate Hard spots, heat checks, blueing discoloration of rotor friction surfaces Glazed rotor friction surfaces Bent or damaged caliper or mounting component Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis . Did you find and correct a condition?Go to Step 9Go to Step 3
3Inspect the brake assist system for the following conditions. Lack of lubrication or excessively worn pushrod or pedal pivots or pivot bushings Bent or damaged pedal pushrod, pedal, or pedal bracket Damaged or improperly operating vacuum booster and/or check valve, if equipped Low power steering fluid level, if equipped with hydraulic boost Improperly tensioned, excessively worn or damaged power steering belt, if equipped with hydraulic boost Restricted return hose from hydraulic booster, if equipped Improperly operating hydraulic booster, if equipped Improperly functioning power steering system, if equipped with a hydraulic booster assembly Contaminated power steering fluid, if equipped with hydraulic boost Adjust, repair or replace components as necessary. Refer to Brake Assist System Diagnosis . Did you find and correct a condition?Go to Step 9Go to Step 4
4Inspect the hydraulic brake system for the following conditions. Improper operation of caliper pistons Contaminated brake fluid Adjust, repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis . Did you find and correct a condition?Go to Step 9Go to Step 5
5Is the vehicle equipped with a drum-in-rotor type of park brake system?Go to Step 6Go to Step 9
6Ensure the park brake shoes are not adjusted too tightly, possibly causing a noise under certain conditions. Are the park brake shoes adjusted too tightly?Go to Step 7Go to Step 9
7Clean and inspect the park brake shoes for excessive wear and/or damage. Inspect the drum portion of the rotors for excessive wear, blueing discoloration, heat spots, and excessive radial runout. If any of these conditions are present, replace the affected components. Adjust the park brake system. Did you find and correct a condition?Go to Step 9Go to Step 8
8Inspect the park brake system for proper operation. Refer to Park Brake System Diagnosis . Did you find and correct a condition?Go to Step 9Go to Diagnostic Starting Point - Hydraulic Brakes
9Install or connect components that were removed or disconnected during diagnosis. 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 2System OK

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. 4: Suspension components that are not operating properly may cause a disturbance to the vehicle during application of the brake system.
  2. 5: Steering components that are not operating properly may cause a disturbance to the vehicle during application of the brake system.
StepActionYesNo
DEFINITION: Vehicle pulls to one side only when braking.
1Were you sent here from the Hydraulic Brake Symptom table?Go to Step 2Go to Diagnostic Starting Point - Hydraulic Brakes
2Inspect the hydraulic brake system for the following conditions. Kinked, pinched or damaged brake pipe or flexible brake hose Sticking or improperly operating caliper piston Brake fluid leak Adjust, repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis . Did you find and correct a condition?Go to Step 6Go to Step 3
3Inspect the disc brake system for the following conditions. Contaminated linings Glazed linings Distorted, cracked or damaged linings on one side Loose, damaged or missing caliper hardware and/or lining hardware Incorrect linings on one side Hard spots, heat checks, blueing discoloration of rotor friction surfaces; possibly due to brake drag Glazed rotor friction surfaces Bent or damaged caliper or mounting component Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis . Did you find and correct a condition?Go to Step 6Go to Step 4
4Inspect the suspension system for the following conditions. Incorrect tire pressures Loose suspension component connections Excessively worn or damaged suspension components Adjust, repair or replace components as necessary. Refer to Diagnostic Starting Point - Suspension General Diagnosis . Did you find and correct a condition?Go to Step 6Go to Step 5
5Inspect the steering system for the following conditions. Loose steering component connections Excessively worn or damaged steering components Adjust, repair or replace components as necessary. Refer to Diagnostic Starting Point - Power Steering System (w/o Electro-Hydraulic Steering) . Did you find and correct a condition?Go to Step 6Go to Diagnostic Starting Point - Hydraulic Brakes
6Install or connect components that were removed or disconnected during diagnosis. 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 2System OK

Test Descriptions

The number below refers to the step number on the diagnostic table.

  1. 4: Suspension components that are not operating properly may cause a disturbance to the vehicle during application of the brake system.
StepActionYesNo
DEFINITION: Braking action or stopping force sensitive or grabbing and/or more pronounced at the front or at the rear axle. Sensitive or grabbing brakes: Excessive brake jump-in force relative to brake pedal input.
1Were you sent here from the Hydraulic Brake Symptom table?Go to Step 2Go to Diagnostic Starting Point - Hydraulic Brakes
2Inspect the hydraulic brake system for the following conditions: Improper operation of caliper pistons Kinked, pinched or damaged brake pipe or flexible brake hose Brake fluid leak Improperly functioning proportion valve, if equipped Improper operation of dynamic rear proportion (DRP) system, if equipped Adjust, repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis . Did you find and correct a condition?Go to Step 6Go to Step 3
3Inspect the disc brake system for the following conditions: Contaminated linings Glazed linings Distorted, cracked or damaged linings Excessively worn linings Aftermarket linings Damaged or excessively worn caliper hardware and/or lining hardware Hard spots, heat checks, blueing discoloration of rotor friction surfaces Glazed rotor friction surfaces Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis . Did you find and correct a condition?Go to Step 6Go to Step 4
4Inspect the suspension system for the following conditions: Loose suspension component connections Excessively worn or damaged suspension components Adjust, repair or replace components as necessary. Refer to Diagnostic Starting Point - Suspension General Diagnosis . Did you find and correct a condition?Go to Step 6Go to Step 5
5Inspect the brake assist system for the following conditions: Binding, bent or damaged pedal pushrod, pedal, or pedal bracket Damaged or improperly operating vacuum booster, if equipped Damaged or improperly operating hydraulic booster, if equipped Adjust, repair or replace components as necessary. Refer to Brake Assist System Diagnosis . Did you find and correct a condition?Go to Step 6Go to Diagnostic Starting Point - Hydraulic Brakes
6Install or connect components that were removed or disconnected during diagnosis. 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 2System OK

Brake Pedal Excessive Travel

StepActionYesNo
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.
1Were you sent here from the Hydraulic Brake Symptom table?Go to Step 2Go to Diagnostic Starting Point - Hydraulic Brakes
2Inspect the travel and feel of brake pedal applies. Perform the following: Apply the brake pedal several times to fully deplete the power reserve. With power reserve depleted, apply the brake pedal with light, steady pressure and hold for 15 seconds. Observe pedal travel and feel. 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. 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
3Inspect 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 Pedal returned to rest slowly after any of the applies Internally damaged flexible brake hoses; hindering fluid return Binding caliper pistons Internal brake fluid leaks; improperly functioning master cylinder Repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis . Re-inspect brake pedal apply travel and feel. Did you find and correct a condition?Go to Step 8Go to Step 4
4Inspect 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 Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis . Re-inspect brake pedal apply travel and feel. Did you find and correct a condition?Go to Step 8Go to Step 5
5Inspect for proper brake pedal travel. Refer to Brake Pedal Travel Measurement and Inspection . Is the brake pedal travel distance within the acceptable limits?Go to Step 7Go to Step 6
6Inspect 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. 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 8Go to Step 7
7Inspect 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 Adjust, repair or replace components as necessary. Refer to Brake Assist System Diagnosis . Did you find and correct a condition?Go to Step 8Go to Diagnostic Starting Point - Hydraulic Brakes
8Install or connect components that were removed or disconnected during diagnosis. 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 2System OK

Brake Pedal Excessive Effort

StepActionYesNo
DEFINITION: Brake pedal requires an increased amount of input from the driver to obtain good braking action and/or stopping distance is increased.
1Were you sent here from the Hydraulic Brake Symptom table?Go to Step 2Go to Diagnostic Starting Point - Hydraulic Brakes
2Inspect the brake assist system for the following conditions: Vacuum leaks, if equipped with vacuum power assist Power steering fluid leaks, if equipped with hydraulic power assist Lack of lubrication, binding or excessively worn pushrod or pedal pivots or pivot bushings Bent or damaged pedal pushrod, pedal, or pedal bracket Damaged or improperly operating brake booster assembly Adjust, repair or replace components as necessary. Refer to Brake Assist System Diagnosis . Did you find and correct a condition?Go to Step 5Go to Step 3
3Inspect the hydraulic brake system for the following conditions: Binding caliper pistons Internally damaged flexible brake hoses; hindering fluid flow External brake fluid leaks Kinked or damaged flexible brake hoses and/or pipes Internal brake fluid leaks; improperly operating master cylinder Poor brake fluid quality; low boiling point Adjust, repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis . Did you find and correct a condition?Go to Step 5Go to Step 4
4Inspect the disc brake system for the following conditions: Excessively worn linings Glazed linings Cracked, distorted or damaged linings Contaminated linings Binding, damaged or excessively worn caliper hardware and/or lining hardware Lack of lubrication or excessive corrosion on metal to metal contact surfaces Excessively worn or corroded rotor friction surfaces Glazed rotor friction surfaces Hard spots, heat checks, blueing discoloration of rotor friction surfaces Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis . Did you find and correct a condition?Go to Step 5Go to Diagnostic Starting Point - Hydraulic Brakes
5Install or connect components that were removed or disconnected during diagnosis. 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 2System OK

Brakes Drag

StepActionYesNo
DEFINITION: Brake system does not fully release or has delayed release; vehicle motion may be hindered by brake system without applying brakes.
1Were you sent here from the Hydraulic Brake Symptom table?Go to Step 2Go to Diagnostic Starting Point - Hydraulic Brakes
2Is the vehicle equipped with an adjustable stop lamp switch and/or an adjustable cruise control release switch?Go to Step 3Go to Step 4
3Inspect the stop lamp switch for proper adjustment to ensure that the brake pedal is fully releasing. Inspect the cruise control release switch, if equipped, for proper adjustment to ensure that the brake pedal is fully releasing. Did you find and correct a condition?Go to Step 14Go to Step 4
4Is the vehicle equipped with a drum-in-rotor type of park brake system?Go to Step 5Go to Step 7
5Ensure the park brake shoes are not adjusted too tightly, possibly causing drag under certain conditions. Are the park brake shoes adjusted too tightly?Go to Step 6Go to Step 7
6Clean and inspect the park brake shoes for excessive wear and/or damage. Inspect the drum portion of the rotors for excessive wear, blueing discoloration and heat spots. If any of these conditions are present, replace the affected components. Adjust the park brake system. Did you find and correct a condition?Go to Step 14Go to Step 7
7Inspect the park brake system for proper operation. Refer to Park Brake System Diagnosis . Did you find and correct a condition?Go to Step 14Go to Step 8
8Inspect the disc brake system for the following conditions: Binding, incorrectly installed or missing caliper hardware and/or lining hardware-Ensure free movement of linings and of caliper, if equipped with sliding type caliper Lack of lubrication or excessive corrosion on metal to metal contact surfaces Distorted or damaged linings Damaged or excessively worn caliper hardware and/or lining hardware Bent or damaged caliper or mounting component Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis . Did you find and correct a condition?Go to Step 14Go to Step 9
9Separate the brake booster pushrod from the brake pedal. Inspect the brake corners to determine if the brake drag condition is still present. Do the brake corners still exhibit the brake drag condition?Go to Step 11Go to Step 10
10Inspect the pushrod for improper positioning and/or damage. Correctly position or replace the pushrod if necessary. Inspect the brake pedal assembly for damage and replace if necessary. Did you complete the repair or replacement?Go to Step 14
11For vacuum boost systems, disconnect the vacuum check valve from the booster to relieve vacuum reserve. Separate the master cylinder from the brake booster. Do not disconnect any brake pipes. Inspect the brake corners to determine if the brake drag condition is still present. Do the brake corners still exhibit the brake drag condition?Go to Step 13Go to Step 12
12Replace the brake booster assembly. Did you complete the replacement?Go to Step 14
13Inspect the hydraulic brake system for the following conditions. Improper operation of caliper pistons Contaminated brake fluid Internally damaged flexible brake hoses; hindering brake release Damaged or improperly operating master cylinder Adjust, repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis . Did you find and correct a condition?Go to Step 14Go to Diagnostic Starting Point - Hydraulic Brakes
14Install or connect components that were removed or disconnected during diagnosis. 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 2System OK

Brake System Slow Release

StepActionYesNo
DEFINITION: Brake system releases and returns to rest slowly; vehicle motion is hindered by brake system briefly after release of brake pedal.
1Were you sent here from the Hydraulic Brake Symptom table?Go to Step 2Go to Diagnostic Starting Point - Hydraulic Brakes
2Inspect the hydraulic brake system for the following conditions: Improper operation of caliper pistons Internally damaged flexible brake hoses; hindering brake release Contaminated brake fluid Damaged or improperly operating master cylinder Adjust, repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis . Did you find and correct a condition?Go to Step 5Go to Step 3
3Inspect the brake assist system for the following conditions: Binding, bent or damaged pedal pushrod, pedal, or pedal bracket Damaged or improperly operating vacuum booster, if equipped Restricted return hose from hydraulic booster, if equipped Damaged or improperly operating hydraulic booster, if equipped Adjust, repair or replace components as necessary. Refer to Brake Assist System Diagnosis . Did you find and correct a condition?Go to Step 5Go to Step 4
4Inspect the disc brake system for the following conditions: Damaged or excessively worn caliper hardware and/or lining hardware Distorted or damaged linings Lack of lubrication or excessive corrosion on metal to metal contact surfaces Bent or damaged caliper or mounting component Adjust, repair or replace components as necessary. Refer to Disc Brake System Diagnosis . Did you find and correct a condition?Go to Step 5Go to Diagnostic Starting Point - Hydraulic Brakes
5Install or connect components that were removed or disconnected during diagnosis. 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 2System OK

Brake Fluid Loss

StepActionYesNo
DEFINITION: Brake fluid level is low not related to lining wear.
1Were you sent here from the Hydraulic Brake Symptom table?Go to Step 2Go to Diagnostic Starting Point - Hydraulic Brakes
2Inspect the following hydraulic brake system components for brake fluid leaks: Flexible brake hose connections; threaded and bolted Flexible brake hose crimp joints Brake pipe fittings Caliper piston seals Wheel cylinder piston seals, if equipped Master cylinder reservoir Master cylinder reservoir low pressure hose, if equipped Brake pressure modulator valve (BPMV) assembly, if equipped Repair or replace components as necessary. Refer to Hydraulic Brake System Diagnosis . Did you find and correct a condition?Go to Step 8Go to Step 3
3Is the vehicle equipped with a vacuum brake booster?Go to Step 4Go to Step 6
4Disconnect the vacuum check valve from the booster to relieve vacuum reserve. Separate the master cylinder from the vacuum brake booster. Do not disconnect any brake pipes. Inspect the rear of the master cylinder for a brake fluid leak. Inspect for brake fluid in the vacuum brake booster. Did you find a brake fluid leak?Go to Step 5Go to Diagnostic Starting Point - Hydraulic Brakes
5Replace the brake master cylinder and the vacuum brake booster. Did you complete the replacement?Go to Step 8
6Wipe clean the external surface of the master cylinder to hydraulic brake booster area, if equipped. Separate the master cylinder from the hydraulic brake booster, if equipped. Do not disconnect any brake pipes. Inspect the rear of the master cylinder for a brake fluid leak. Did you find a brake fluid leak?Go to Step 7Go to Diagnostic Starting Point - Hydraulic Brakes
7Replace the brake master cylinder. Did you complete the replacement?Go to Step 8
8Install or connect components that were removed or disconnected during diagnosis. Road test the vehicle to confirm proper operation. Refer to Brake System Vehicle Road Test . Is the condition still present?Go to Step 2System OK

The numbers below refer to the step numbers on the diagnostic table.

  1. 9: Lubricant leaks from non-brake system components may come in contact with and contaminate brake system components.
  2. 10: Lubricant leaks from non-brake system components may come in contact with and contaminate brake system components.
  1. 13: Disc brake rotor thickness variation that exceeds the maximum acceptable level can cause brake pulsation.
  1. 17: Disc brake rotor thickness variation that exceeds the maximum acceptable level can cause brake pulsation.
  1. 20: Disc brake rotor assembled lateral runout (LRO) that exceeds the maximum acceptable level can lead to thickness variation.
StepActionYesNo
DEFINITION: This diagnostic table is designed to diagnose ONLY the components of the DISC brake system in order to determine if the DISC brake system is operating properly. You will be directed by the appropriate Symptom table to go to other brake system diagnostic tables as appropriate.
1Were you sent here from a Brake Symptom table?Go to Step 2Go to Diagnostic Starting Point - Hydraulic Brakes
2Visually inspect the disc brake pads for the following conditions: Refer to Brake Pad Inspection (JL9, J55, J56) or Brake Pad Inspection (J57) . Lining thickness below specifications Uneven and/or abnormal wear - edge-to-edge and/or side-to-side Looseness or damage - including pad hardware Evidence of contamination from an external substance Did you find any conditions to indicate a concern with any of the front and/or rear disc brake pads?Go to Step 3Go to Step 12
3Are any of the front and/or rear disc brake pads contaminated?Go to Step 8Go to Step 4
4Are any of the front and/or rear disc brake pads worn unevenly?Go to Step 7Go to Step 5
5Are any of the front and/or rear disc brake pads and/or pad hardware loose or damaged?Go to Step 7Go to Step 6
6Remove and inspect the worn disc brake pads for glazing, looseness, heat spots, or damage. Replace the worn disc brake pads as a complete axle set. Refer to Front Disc Brake Pads Replacement (JL9, J55) or Front Disc Brake Pads Replacement (J56) or Front Disc Brake Pads Replacement (J57) and/or Rear Disc Brake Pads Replacement (JL9, J55) or Rear Disc Brake Pads Replacement (J56) or Rear Disc Brake Pads Replacement (J57) . Did you complete the inspection and replacement?Go to Step 12
7CAUTION: Support the brake caliper with heavy mechanic wire, or equivalent, whenever it is separated from its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak. NOTE: Do NOT disconnect the hydraulic brake flex hoses from the calipers. Remove the front and/or rear disc brake calipers, as appropriate, from the mounting brackets and support the calipers. Refer to Front Brake Caliper Replacement (JL9, J55) or Front Brake Caliper Replacement (J56) or Front Brake Caliper Replacement (J57) and/or Rear Brake Caliper Replacement (JL9, J55) or Rear Brake Caliper Replacement (J56) or Rear Brake Caliper Replacement (J57) . Inspect the disc brake caliper mounting bracket and the mounting/sliding hardware for the following conditions: Refer to Front Disc Brake Mounting and Hardware Inspection and/or Rear Disc Brake Mounting and Hardware Inspection . Binding or seized hardware Worn, damaged, or missing hardware components Loose, bent, cracked, or damaged caliper mounting bracket Replace components as required. Refer to the following procedures, as required: Front Brake Caliper Bracket Replacement Rear Brake Caliper Bracket Replacement Front Disc Brake Hardware Replacement (JL9, J55) Front Disc Brake Hardware Replacement (J56) Front Disc Brake Hardware Replacement (J57) Rear Disc Brake Hardware Replacement (JL9, J55) Rear Disc Brake Hardware Replacement (J56) Rear Disc Brake Hardware Replacement (J57) Replace the unevenly-worn, loose, or damaged disc brake pads as a complete axle set. Refer to Front Disc Brake Pads Replacement (JL9, J55) or Front Disc Brake Pads Replacement (J56) or Front Disc Brake Pads Replacement (J57) and/or Rear Disc Brake Pads Replacement (JL9, J55) or Rear Disc Brake Pads Replacement (J56) or Rear Disc Brake Pads Replacement (J57) . Did you complete the inspection and replacement?Go to Step 12
8Inspect the disc brake calipers, brake hoses, and brake pipes for evidence of an external brake fluid leak. Replace any components found to be leaking brake fluid. Refer to the following procedures as required: Front Brake Caliper Overhaul (JL9, J55) Front Brake Caliper Overhaul (J56, J57) or Front Brake Caliper Replacement (JL9, J55) Front Brake Caliper Replacement (J56) Front Brake Caliper Replacement (J57) Rear Brake Caliper Overhaul (JL9, J55) Rear Brake Caliper Overhaul (J56, J57) or Rear Brake Caliper Replacement (JL9, J55) Rear Brake Caliper Replacement (J56) Rear Brake Caliper Replacement (J57) Front Brake Hose Replacement (JL9, J55) Front Brake Hose Replacement (J56) Front Brake Hose Replacement (J57) Rear Brake Hose Replacement (JL9, J55) Rear Brake Hose Replacement (J56) Rear Brake Hose Replacement (J57) Brake Pipe Replacement Did you find and correct the source of the leak causing contamination of the pads?Go to Step 11Go to Step 9
9Inspect the wheel drive shaft outer seals for damage and evidence of a grease leak. Replace any wheel drive shaft seal that is found to be leaking grease which may be the source of the contamination to the pads. Refer to Wheel Drive Shaft Outer Joint and Boot Replacement . Did you find and correct the source of the leak causing contamination of the pads?Go to Step 11Go to Step 10
10Inspect the automatic transmission cooling system lines, if equipped, for damage and evidence of an external fluid leak which may be the source of the contamination to the pads. Inspect the power steering system hoses for damage and evidence of an external fluid leak which may be the source of the contamination to the pads. Replace any components found to be leaking fluid which may be the source of the contamination to the pads. Did you find and correct the source of the leak causing contamination of the pads?Go to Step 11
11Clean the remaining disc brake system components to remove any traces of the contaminant. CAUTION: Support the brake caliper with heavy mechanic wire, or equivalent, whenever it is separated from its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak. NOTE: Do NOT disconnect the hydraulic brake flex hoses from the calipers. Remove the front and/or rear disc brake calipers, as appropriate, from the mounting brackets and support the calipers. Refer to Front Brake Caliper Replacement (JL9, J55) or Front Brake Caliper Replacement (J56) or Front Brake Caliper Replacement (J57) and/or Rear Brake Caliper Replacement (JL9, J55) or Rear Brake Caliper Replacement (J56) or Rear Brake Caliper Replacement (J57) . Inspect the disc brake caliper mounting/sliding hardware for the following conditions: Refer to Front Disc Brake Mounting and Hardware Inspection and/or Rear Disc Brake Mounting and Hardware Inspection . Binding or seized hardware Distorted, worn, damaged, or missing hardware components Replace the caliper mounting/sliding hardware components as required. Refer to Front Disc Brake Hardware Replacement (JL9, J55) or Front Disc Brake Hardware Replacement (J56) or Front Disc Brake Hardware Replacement (J57) and/or Rear Disc Brake Hardware Replacement (JL9, J55) or Rear Disc Brake Hardware Replacement (J56) or Rear Disc Brake Hardware Replacement (J57) . Replace the contaminated disc brake pads as a complete axle set. Refer to Front Disc Brake Pads Replacement (JL9, J55) or Front Disc Brake Pads Replacement (J56) or Front Disc Brake Pads Replacement (J57) and/or Rear Disc Brake Pads Replacement (JL9, J55) or Rear Disc Brake Pads Replacement (J56) or Rear Disc Brake Pads Replacement (J57) . Did you complete the cleaning, inspection, and replacement?Go to Step 12
12Check the thickness of each of the disc brake rotors. NOTE: Make the following determination AND ANSWER the question INDIVIDUALLY for EACH rotor. Make a determination for each brake rotor if the rotor can be REFINISHED and REMAIN ABOVE the minimum requirements. Refer to Brake Rotor Thickness Variation Measurement (JL9, J55, J56) or Brake Rotor Thickness Variation Measurement (J57) .Does the disc brake rotor meet the minimum requirements for REFINISHING?Go to Step 13Go to Step 16
13NOTE: Perform the following inspection AND ANSWER the question INDIVIDUALLY for EACH rotor. Inspect each of the disc brake rotors for thickness variation that exceeds the maximum acceptable level. Refer to Brake Rotor Thickness Variation Measurement (JL9, J55, J56) or Brake Rotor Thickness Variation Measurement (J57) .Does the brake rotor exhibit thickness variation that exceeds the maximum acceptable level?Go to Step 15Go to Step 14
14Inspect each of the disc brake rotors for the following surface and wear conditions: Refer to Brake Rotor Surface and Wear Inspection (JL9, J55, J56) or Brake Rotor Surface and Wear Inspection (J57) . Heavy rust and/or pitting Cracks and/or heat spots Excessive blueing discoloration Deep or excessive scoring beyond maximum acceptable level NOTE: Make the following determination AND ANSWER the question INDIVIDUALLY for EACH rotor. Make a determination for each brake rotor if the rotor requires refinishing based upon the results of the inspection. If the brake rotor exhibits any of the conditions listed previously, it requires refinishing. Does the brake rotor require REFINISHING?Go to Step 15Go to Step 20
15Refinish the brake rotor. Refer to Brake Rotor Refinishing . Inspect the brake rotor thickness. Refer to Brake Rotor Thickness Variation Measurement (JL9, J55, J56) or Brake Rotor Thickness Variation Measurement (J57) . Were you able to REFINISH the brake rotor within the minimum requirements?Go to Step 20Go to Step 19
16Is the brake rotor at or below the DISCARD requirements?Go to Step 19Go to Step 17
17NOTE: Perform the following inspection AND ANSWER the question INDIVIDUALLY for EACH rotor. Inspect each of the disc brake rotors for thickness variation that exceeds the maximum acceptable level. Refer to Brake Rotor Thickness Variation Measurement (JL9, J55, J56) or Brake Rotor Thickness Variation Measurement (J57) .Does the brake rotor exhibit thickness variation that exceeds the maximum acceptable level?Go to Step 19Go to Step 18
18Inspect each of the disc brake rotors for the following surface and wear conditions: Refer to Brake Rotor Surface and Wear Inspection (JL9, J55, J56) or Brake Rotor Surface and Wear Inspection (J57) . Heavy rust and/or pitting Cracks and/or heat spots Excessive blueing discoloration Deep or excessive scoring beyond maximum acceptable level NOTE: Make the following determination AND ANSWER the question INDIVIDUALLY for EACH rotor. Make a determination for each brake rotor if the rotor requires replacement based upon the results of the inspection. If the brake rotor exhibits any of the conditions listed previously, it requires replacement. Does the brake rotor require REPLACEMENT?Go to Step 19Go to Step 20
19NOTE: Whenever a brake rotor is replaced, the assembled lateral runout (LRO) of the rotor must be measured to ensure optimum performance of the disc brakes. Replace the brake rotor. Refer to Front Brake Rotor Replacement (JL9, J55, J56) or Front Brake Rotor Replacement (J57) or Rear Brake Rotor Replacement (JL9, J55, J56) or Rear Brake Rotor Replacement (J57) .Did you complete the replacement?Go to Step 22
20NOTE: Perform the following inspection AND ANSWER the question INDIVIDUALLY for EACH rotor. Inspect each of the disc brake rotors for assembled LRO that exceeds the maximum acceptable level. Refer to Brake Rotor Assembled Lateral Runout Measurement (JL9, J55, J56) or Brake Rotor Assembled Lateral Runout Measurement (J57) .Does the brake rotor exhibit assembled LRO that exceeds the maximum acceptable level?Go to Step 21Go to Step 22
21Correct the LRO for each brake rotor that was determined to have LRO exceeding the maximum acceptable level. Refer to Brake Rotor Assembled Lateral Runout Correction . Did you complete the operation?Go to Step 22
22Install or connect components that were removed or disconnected during diagnosis. Did you complete the operation?Disc Brake System OK Return to Symptom Table
CAUTION
Support the brake caliper with heavy mechanic wire, or equivalent, whenever it is separated from its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak.
NOTE
Do NOT disconnect the hydraulic brake flex hoses from the calipers.
CAUTION
Support the brake caliper with heavy mechanic wire, or equivalent, whenever it is separated from its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak.
NOTE
Do NOT disconnect the hydraulic brake flex hoses from the calipers.
NOTE
Make the following determination AND ANSWER the question INDIVIDUALLY for EACH rotor.
NOTE
Perform the following inspection AND ANSWER the question INDIVIDUALLY for EACH rotor.
NOTE
Make the following determination AND ANSWER the question INDIVIDUALLY for EACH rotor.
NOTE
Perform the following inspection AND ANSWER the question INDIVIDUALLY for EACH rotor.
NOTE
Make the following determination AND ANSWER the question INDIVIDUALLY for EACH rotor.
NOTE
Whenever a brake rotor is replaced, the assembled lateral runout (LRO) of the rotor must be measured to ensure optimum performance of the disc brakes.
NOTE
Perform the following inspection AND ANSWER the question INDIVIDUALLY for EACH rotor.
StepActionYesNo
DEFINITION: This diagnostic table is designed to diagnose ONLY the components of the HYDRAULIC brake system in order to determine if the HYDRAULIC brake system is operating properly. You will be directed by the appropriate Symptom table to go to other brake system diagnostic tables as appropriate.
1Were you sent here from a Brake Symptom table?Go to Step 2Go to Diagnostic Starting Point - Hydraulic Brakes
2Inspect and adjust the brake fluid level in the brake master cylinder. Refer to Master Cylinder Reservoir Filling . Was the brake fluid level low?Go to Step 3Go to Step 4
3Inspect the brake fluid for the following conditions, indicating brake fluid contamination: Fluid separation, indicating two types of fluid are present Swirled appearance - oil-based substance Layered appearance - silicone-based substance Fluid discoloration Cloudy appearance - moisture Dark appearance/suspended particles in fluid - dirt, rust, corrosion, brake dust Inspect the master cylinder reservoir cap diaphragm and the reservoir-to-master cylinder grommets for swelling, indicating fluid contamination. Do any of the above conditions exist?Go to Step 5Go to Step 6
4Inspect the brake fluid for the following conditions, indicating brake fluid contamination: Fluid separation, indicating two types of fluid are present Swirled appearance - oil-based substance Layered appearance - silicone-based substance Fluid discoloration Cloudy appearance - moisture Dark appearance/suspended particles in fluid - dirt, rust, corrosion, brake dust Inspect the master cylinder reservoir cap diaphragm and the reservoir-to-master cylinder grommets for swelling, indicating fluid contamination. Do any of the above conditions exist?Go to Step 5Go to Step 12
5Flush the hydraulic brake system. Refer to Hydraulic Brake System Flushing . If the brake fluid WAS contaminated with an oil-based or a silicone-based fluid, indicated by fluid separation and/or a swollen master cylinder reservoir cap diaphragm and/or swollen reservoir-to-master cylinder grommets, perform the following steps. Refer to the procedures indicated. Remove ALL of the following components listed. Each component contains internal rubber seals/linings which have been contaminated. Clean out the hydraulic brake pipes using denatured alcohol, or equivalent. Dry the brake pipes using non-lubricated, filtered air. Repair or replace ALL of the following components listed. Each component contains internal rubber seals/linings which have been contaminated. Master Cylinder Replacement Brake master cylinder reservoir: Clean the brake master cylinder reservoir using denatured alcohol, or equivalent, then dry the reservoir using non-lubricated, filtered air, or if necessary, replace the brake master cylinder reservoir. Replace the brake master cylinder reservoir cap diaphragm. Front Brake Hose Replacement (JL9, J55) Front Brake Hose Replacement (J56) Front Brake Hose Replacement (J57) Rear Brake Hose Replacement (JL9, J55) Rear Brake Hose Replacement (J56) Rear Brake Hose Replacement (J57) Front Brake Caliper Overhaul (JL9, J55) Front Brake Caliper Overhaul (J56, J57) or Front Brake Caliper Replacement (JL9, J55) Front Brake Caliper Replacement (J56) Front Brake Caliper Replacement (J57) Rear Brake Caliper Overhaul (JL9, J55) Rear Brake Caliper Overhaul (J56, J57) or Rear Brake Caliper Replacement (JL9, J55) Rear Brake Caliper Replacement (J56) Rear Brake Caliper Replacement (J57) Brake Pressure Modulator Valve Replacement If the brake fluid was NOT contaminated with an oil-based fluid, but WAS contaminated with water or dirt, rust, corrosion, and/or brake dust, replace the brake master cylinder reservoir cap diaphragm which may have allowed moisture or dirt to enter the system. Refill and bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding (Pressure) or Hydraulic Brake System Bleeding (Manual) . Did you complete the operation and any required repairs and/or replacements?Go to Step 9
6Inspect the following hydraulic brake system components for external fluid leaks Repair or replace any of the components found to be leaking brake fluid. Refer to the appropriate procedures: Master Cylinder Replacement Brake master cylinder reservoir cap diaphragm Front Brake Hose Replacement (JL9, J55) Front Brake Hose Replacement (J56) Front Brake Hose Replacement (J57) Rear Brake Hose Replacement (JL9, J55) Rear Brake Hose Replacement (J56) Rear Brake Hose Replacement (J57) Brake Pipe Replacement Front Brake Caliper Overhaul (JL9, J55) Front Brake Caliper Overhaul (J56, J57) or Front Brake Caliper Replacement (JL9, J55) Front Brake Caliper Replacement (J56) Front Brake Caliper Replacement (J57) Rear Brake Caliper Overhaul (JL9, J55) Rear Brake Caliper Overhaul (J56, J57) or Rear Brake Caliper Replacement (JL9, J55) Rear Brake Caliper Replacement (J56) Rear Brake Caliper Replacement (J57) Brake Pressure Modulator Valve Replacement If you repaired or replaced any of the brake system components listed, bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding (Pressure) or Hydraulic Brake System Bleeding (Manual) . While bleeding the hydraulic brake system, observe for the following conditions: The presence of air in the system at a bleeder valve location other than at the repair location, except if the brake master cylinder was replaced An unrestricted and even flow of brake fluid per axle during the bleeding procedure Did you find and correct a condition?Go to Step 7Go to Step 12
7Was there air in the system at a bleeder valve location other than at the repair location, except if the brake master cylinder was replaced?Go to Step 19Go to Step 8
8Was the flow of brake fluid unrestricted and even per axle during the bleeding procedure?Go to Step 9Go to Step 10
9Inspect the hydraulic function of the brake calipers for proper operation. Refer to Hydraulic Brake Component Operation Visual Inspection . Was the hydraulic function of the brake calipers operating properly?Go to Step 21Go to Step 14
10Was the flow of brake fluid restricted or uneven through front axle hydraulic components during the bleeding procedure?Go to Step 13Go to Step 11
11Was the flow of brake fluid restricted or uneven through rear axle hydraulic components during the bleeding procedure?Go to Step 17
12Inspect the hydraulic function of the brake calipers for proper operation. Refer to Hydraulic Brake Component Operation Visual Inspection . Was the hydraulic function of the brake calipers operating properly?Go to Step 15Go to Step 13
13Determine if the brake caliper is restricting the flow of brake fluid and/or not operating properly: Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation . Open the suspected caliper bleeder valve. Using a large C-clamp, compress the caliper piston and observe for an unrestricted flow of brake fluid and for free movement of the caliper piston. Close the caliper bleeder valve. Was the flow of brake fluid unrestricted and did the caliper piston move freely?Go to Step 17Go to Step 14
14Repair or replace any brake caliper that was not operating properly. Refer to the appropriate procedure. Front Brake Caliper Overhaul (JL9, J55) or Front Brake Caliper Overhaul (J56, J57) or Front Brake Caliper Replacement (JL9, J55) or Front Brake Caliper Replacement (J56) or Front Brake Caliper Replacement (J57) Rear Brake Caliper Overhaul (JL9, J55) or Rear Brake Caliper Overhaul (J56, J57) or Rear Brake Caliper Replacement (JL9, J55) or Rear Brake Caliper Replacement (J56) or Rear Brake Caliper Replacement (J57) Did you complete the repair and/or replacement?Go to Step 21
15Bleed the hydraulic brake system to observe for the presence of air in the system and to observe for an unrestricted and even flow of brake fluid per axle during the bleeding procedure. Refer to Hydraulic Brake System Bleeding (Pressure) or Hydraulic Brake System Bleeding (Manual) . Was there air in the system?Go to Step 19Go to Step 16
16Was the flow of brake fluid unrestricted and even per axle during the bleeding procedure?Go to Step 21Go to Step 17
17Inspect the hydraulic brake pipes and flexible brake hoses for signs of a fluid restriction; such as being bent, kinked, pinched or damaged. Refer to Brake Pipe and Hose Inspection . Replace any of the hydraulic brake pipes and/or flexible brake hoses found to be bent, kinked, pinched, or damaged. Refer to the following procedures as necessary: Front Brake Hose Replacement (JL9, J55) Front Brake Hose Replacement (J56) Front Brake Hose Replacement (J57) Rear Brake Hose Replacement (JL9, J55) Rear Brake Hose Replacement (J56) Rear Brake Hose Replacement (J57) Brake Pipe Replacement If none of the hydraulic brake pipes or flexible brake hoses were visibly bent, kinked, pinched, or damaged, replace the hydraulic brake flex hose at the restricted location. Did you find and correct a condition?Go to Step 21Go to Step 18
18Replace the brake pressure modulator valve (BPMV), in order to correct the hydraulic brake dynamic rear proportioning mechanical operation. Refer to Brake Pressure Modulator Valve Replacement . Did you complete the replacement?Go to Step 21
19Inspect the hydraulic brake system components for brake fluid seepage at a seal and/or fitting location, which may have drawn air into the system. Inspect the hydraulic brake system components for evidence of a recent repair, which may have introduced air into the system. Repair or replace any of the components found to be installed incorrectly or seeping brake fluid. Did you find and correct a condition?Go to Step 21Go to Step 20
20Inspect the brake master cylinder for internal fluid leaks. Refer to Brake System Internal Leak Test . Replace the brake master cylinder if it is found to be leaking brake fluid internally. Refer to Master Cylinder Replacement . Did you find and correct a condition?Go to Step 21Return to Symptom Table
21Install or connect components that were removed or disconnected during diagnosis. Did you complete the operation?Hydraulic Brake System OK Return to Symptom Table

Brake Assist System Diagnosis

StepActionYesNo
DEFINITION: This diagnostic table is designed to diagnose ONLY the components of the brake ASSIST system in order to determine if the brake ASSIST system is operating properly. You will be directed by the appropriate Symptom table to go to other brake system diagnostic tables as appropriate.
1Were you sent here from a Brake Symptom table?Go to Step 3Go to Step 2
2Were you sent here directly from an electrical diagnostic to investigate vacuum as a possible concern?Go to Step 5Go to Diagnostic Starting Point - Hydraulic Brakes
3Inspect for proper brake pedal travel. Refer to Brake Pedal Travel Measurement and Inspection . Is the brake pedal travel distance within the acceptable limits?Go to Step 5Go to Step 4
4Inspect 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 excessive wear and/or damage and inspect the brake pedal for a misaligned, bent and/or damaged condition. 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 5Go to Hydraulic Brake System Diagnosis to check for internal and external fluid leaks and air in the hydraulic brake system
5Check the engine vacuum source that supplies vacuum to the vacuum brake booster. Refer to Brake System Vacuum Source Test . Is the vacuum reading within the acceptable limits?Go to Step 6Go to Engine Controls Diagnostics Information to check for vacuum issues, including vacuum pump operation, if equipped
6Does the condition occur during cold start-up conditions?Go to Step 7Go to Step 8
7Check engine vacuum, and vacuum pump operation, if equipped, under the same cold start-up conditions. Refer to appropriate Engine Controls Diagnostics article. Did you find and correct a condition?Go to Step 22Go to Step 9
8During the vacuum source test, did the vacuum booster check valve operate properly?Go to Step 10Go to Step 9
9Replace the vacuum booster check valve. Refer to Power Brake Booster Vacuum Check Valve and Hose Replacement . Did you complete the replacement?Go to Step 10
10If equipped with a booster mounted separate vacuum sensor, inspect the vacuum sensor grommet for cracks, cuts, dry-rot, or damage. Does the vacuum sensor grommet exhibit any of the conditions listed?Go to Step 11Go to Step 12
11Replace the vacuum sensor grommet. Did you complete the replacement?Go to Step 12
12If the vehicle is equipped with a vacuum sensor, install a scan tool. Using the Data Display function, determine if brake booster vacuum sensor data is available within either the chassis brake controls area or the powertrain engine controls area. Is vacuum sensor data available through the scan tool?Go to Step 13Go to Step 16
13Perform the vacuum booster leak-down test using a scan tool: Release the brake pedal. Accelerate the engine to approximately 3000 RPM, then release the throttle. Wait 2-3 seconds and repeat once. Turn the ignition OFF. Turn the ignition ON. Do not start the engine. Observe and record the vacuum sensor reading on the scan tool over a period of 60 seconds. IMPORTANT: Vacuum readings will decrease by approximately 2.7 kPa (0.8 Hg) for every 305 m (1000 ft) of elevation above sea level. Determine the rate of vacuum leak. Specification: Maximum allowable vacuum leak rate: 10 kPa (3 in Hg) in 60 seconds Was the rate of vacuum leak within the specified allowable range?Go to Step 18Go to Step 14
14Deplete the vacuum reserve by pressing the brake pedal several times, or by removing the vacuum booster check valve. Separate the master cylinder from the vacuum brake booster. Do not disconnect any brake pipes. Refer to Master Cylinder Replacement . If equipped with a vacuum seal on the rear of the master cylinder, inspect the seal for damage and correct positioning on the master cylinder. Replace the vacuum seal as necessary. Carefully reinstall the master cylinder to the brake booster. Refer to Master Cylinder Replacement . Did you complete the operation?Go to Step 15
15Perform the vacuum booster leak-down test using a scan tool: Release the brake pedal. Accelerate the engine to approximately 3000 RPM, then release the throttle. Wait 2-3 seconds and repeat once. Turn the ignition OFF. Turn the ignition ON. Do not start the engine. Observe and record the vacuum sensor reading on the scan tool over a period of 60 seconds. IMPORTANT: Vacuum readings will decrease by approximately 2.7 kPa (0.8 Hg) for every 305 m (1000 ft) of elevation above sea level. Determine the rate of vacuum leak. Specification: Maximum allowable vacuum leak rate: 10 kPa (3 in Hg) in 60 seconds Was the rate of vacuum leak within the specified allowable range?Go to Step 22Go to Step 21
16Separate the master cylinder from the vacuum brake booster. Do not disconnect any brake pipes. Before removing the master cylinder, first deplete the vacuum by removing the check valve or applying the brake pedal several times. Refer to Master Cylinder Replacement . If equipped with a vacuum seal on the rear of the master cylinder, inspect the seal for damage and correct positioning on the master cylinder. If equipped with a vacuum seal that is part of the booster, inspect the seal for damage. Does the vacuum seal exhibit any of the conditions listed?Go to Step 17Go to Step 18
17If equipped with a vacuum seal on the rear of the master cylinder, replace the vacuum seal as necessary. Ensure the seal is positioned correctly during installation. If equipped with a vacuum seal that requires replacement and which is part of the booster, the booster assembly must be replaced. Carefully reinstall the master cylinder to the brake booster. Refer to Master Cylinder Replacement . Did you complete the replacement?Go to Step 18
18Perform the vacuum boost functional test: If still separated, reinstall the master cylinder to the booster. Refer to Master Cylinder Replacement . If the engine was started after reinstalling the master cylinder to the booster, perform the following: With the engine OFF, depress the brake pedal several times to deplete the vacuum reserve. Depress and maintain moderate foot pressure on the brake pedal. Start the engine and observe pedal operation. Observe for audible vacuum leaks. The brake pedal should fall slightly, then hold. Is there an audible vacuum leak coming from the brake pedal area?Go to Step 21Go to Step 19
19Did the brake pedal fall slightly after the engine was started, then hold?Go to Step 20Go to Step 21
20Perform the vacuum booster leak-down test: Release the brake pedal. Accelerate the engine to approximately 3000 RPM, then release the throttle. Wait 2-3 seconds and repeat once. Turn the ignition OFF. Wait 60 seconds. Depress the brake pedal 2 times to check for vacuum booster available vacuum reserve. Observe pedal effort. Both pedal applies should be assisted The amount of assist could diminish slightly with the second apply Were both pedal applies power assisted?Go to Step 22Go to Step 21
21Replace the vacuum brake booster. Refer to Power Vacuum Brake Booster Replacement . Did you complete the replacement?Go to Step 22
22Install or connect any components that were removed or disconnected during diagnosis. Did you complete the operation?Brake Assist System OK Return to Symptom Table
IMPORTANT
Vacuum readings will decrease by approximately 2.7 kPa (0.8 Hg) for every 305 m (1000 ft) of elevation above sea level.
IMPORTANT
Vacuum readings will decrease by approximately 2.7 kPa (0.8 Hg) for every 305 m (1000 ft) of elevation above sea level.

Preliminary Inspections

  1. Visually inspect easily accessible brake system components for obvious damage and/or leaks which may indicate that the vehicle should not be driven until further inspections have been completed.
  2. Inspect the brake master cylinder reservoir fluid level and adjust only if necessary for brake system road testing. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) .
  3. Inspect the tire inflation pressures and adjust as necessary.
  4. Inspect the tire tread patterns to ensure that they are the same or very similar, especially per axle.
  5. Ensure that the vehicle is not loaded unevenly prior to brake system road testing.

Road Testing Procedure

WARNINGRoad test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage.
  1. Start the engine and allow it to idle.
  2. Check to see if the brake system warning lamp remains illuminated.
  3. If the brake system warning lamp remains illuminated, DO NOT proceed to test drive the vehicle until it is diagnosed and repaired. Refer to «Symptoms - Hydraulic Brakes»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__symptoms-hydraulic-brakes) .
  4. Select a smooth, dry, clean and level road or large lot that is as free of traffic and obstacles as possible for brake system low speed road testing.
  5. With the transmission in PARK, lightly apply the brake pedal. Observe both the pedal feel and the pedal travel.
  6. If the brake pedal apply felt spongy, or the pedal travel was excessive, DO NOT drive the vehicle until it is repaired.
  7. If the brake pedal apply did not feel spongy and the pedal travel was not excessive, proceed to step 8.
  8. Release and apply the brakes.
  9. While continuing to apply the brakes, shift the transmission into DRIVE, release the brakes and allow the engine to idle the vehicle away from the stopped position. Observe for a slow release of the brake system.
  10. With the aid of an assistant to observe the vehicle's performance from outside of the vehicle, drive the vehicle at a low speed and lightly apply the brakes while driving past the assistant. Have the assistant observe for brake system noise from the side of the vehicle closest to them, while you observe both the pedal effort and the pedal travel.
  11. If the brake pedal apply effort was excessive, or the pedal travel was excessive, DO NOT continue to test drive the vehicle until it is repaired.
  12. If the brake pedal apply effort was not excessive and the pedal travel was not excessive, proceed to step 13.
  13. Drive the vehicle in the opposite direction, at the same low speed and lightly apply the brakes while driving past the assistant. Have the assistant observe for brake system noise from the side of the vehicle closest to him.
  14. Drive the vehicle at a low speed and shift the transmission into NEUTRAL without applying the brakes. Observe for a rapid deceleration in vehicle speed, indicating possible brake drag.
  15. Select a smooth, dry, clean and level road that is as free of heavy traffic as possible for brake system moderate speed road testing.
  16. Drive the vehicle at a moderate speed. Observe for a pull and/or incorrect tracking of the vehicle without the brakes applied.
  17. While continuing to drive the vehicle at a moderate speed, perform several light applies of the brakes. Observe the pedal effort and the pedal travel, observe for brake system noise, pulsation and/or brake drag.
  18. If the brake pedal apply effort was excessive, or the pedal travel was excessive, DO NOT continue to test drive the vehicle until it is repaired.
  19. If the brake pedal apply effort was not excessive and the pedal travel was not excessive, proceed to step 20.
  20. While continuing to drive the vehicle at a moderate speed, perform several moderate applies of the brakes. Observe the pedal effort and the pedal travel, observe for brake system pulsation and/or uneven braking action - either side to side, or front to rear. A small amount of vehicle front end dip is expected during a moderate apply of the brakes.
  21. If the brake pedal apply effort was excessive, or the pedal travel was excessive, DO NOT continue to test drive the vehicle until it is repaired.

Tools Required

J 28662 Brake Pedal Effort Gauge. See Special Tools .

  1. With the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort increases significantly, in order to deplete the brake booster power reserve.
  2. Install the J 28662 to the brake pedal. See «Special Tools»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  3. Measure and record the distance (1) from the brake pedal to the rim of the steering wheel; note the points of measurement.
  4. Apply and maintain the brakes with 310 N (70 lb) of force to the brake pedal, as indicated on the J 28662 . See «Special Tools»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  5. While maintaining 310 N (70 lb) of force to the brake pedal, measure and record the distance (2) from the same point on the brake pedal to the same point on the rim of the steering wheel.
  6. Release the brakes and repeat steps 4 and 5 to obtain a second measurement. After obtaining a second measurement, proceed to step 7.
  7. Average the first and second measurements recorded during the two applies of the brakes.
  8. Subtract the initial measurement, un-applied (1), from the averaged, applied measurement (2) to obtain the brake pedal travel distance. Specification: Maximum brake pedal travel - measured with the ignition OFF, brake booster power assist depleted, and the brakes cool: 70 mm (2.75 in).

Brake System Vacuum Source Test

  1. Disconnect the engine vacuum hose from the vacuum brake booster check valve.
  2. Install a vacuum gage to the engine vacuum hose.
  3. Start the engine and allow the engine to idle until normal operating temperatures are reached.
  4. With the vehicle in PARK, the engine idling, and the air conditioning (A/C) system OFF, check to see if the engine vacuum reading is within the specified normal engine vacuum range. Specification: 47-68 kPa (14-20 in Hg)
  5. Turn the ignition OFF.
  6. If the engine vacuum reading is within the specified normal range, proceed to step 10.
  7. If the engine vacuum reading is NOT within the specified normal range, inspect the engine vacuum hose for the following conditions: Loose connection to the engine Collapse, deformation or contamination Cracks, cuts, dry-rot
  8. If any of these conditions were found with the engine vacuum hose, replace the hose, then repeat steps 2-4.
  9. If none of these conditions were found with the engine vacuum hose, then there is an engine vacuum source problem, check the engine vacuum system.
  10. Remove the vacuum brake booster check valve from the booster.
  11. Install the check valve to the engine vacuum hose.
  12. Install the vacuum gage to the check valve.
  13. Start the engine and allow the engine to idle in PARK with the A/C system OFF, until normal operating temperatures are reached.
  14. Turn the ignition OFF.
  15. Check to see if the engine vacuum reading is maintained within the specified normal engine vacuum range. Specification: 47-68 kPa (14-20 in Hg)
  16. If the engine vacuum reading is maintained within the specified normal range, proceed to step 18.
  17. If the engine vacuum reading is NOT maintained within the specified normal range, replace the brake booster check valve, then repeat steps 11-15.
  18. Inspect the brake booster check valve grommet for the following conditions: Loose connection to the vacuum brake booster Deformation or contamination Cracks, cuts, dry-rot
  19. If any of these conditions were found with the check valve grommet, replace the grommet.

Brake System External Leak Inspection

WARNINGRefer to Brake Fluid Irritant Warning .
  1. In order to inspect for external brake fluid leaks, first check the fluid level in the master cylinder. While a slight brake fluid level drop can be considered a normal condition due to brake lining wear, a very low level may indicate a brake fluid leak in the hydraulic system.
  2. If the fluid level is abnormally low, adjust the brake fluid level. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) .
  3. Start the engine and allow it to idle.
  4. Apply constant, moderate foot pressure to the brake pedal. If the brake pedal gradually falls away while under foot pressure, there may be a brake fluid leak.
  5. Turn OFF the ignition.
  6. Visually inspect the following brake system components for brake fluid leaks, excessive corrosion, and damage. Give particular attention to all brake pipe and flexible hose connections to ensure that there are not any slight brake fluid leaks - even though the brake pedal may feel firm and hold steady: Master cylinder brake pipe fittings All brake pipe connections Brake pipes Brake hoses and connections Brake calipers and/or wheel cylinders, if equipped
  7. While slight dampness around the master cylinder reservoir can be considered acceptable, brake fluid leaking from any of the brake system components requires immediate attention. If any of these components exhibit signs of brake fluid leakage, repair or replace those components. After the repair or replacement, reinspect the hydraulic brake system to assure proper function.

Brake System Internal Leak Test

WARNINGRefer to Brake Fluid Irritant Warning .
  1. Start the engine and allow it to idle.
  2. Apply light, steady pressure to the brake pedal. Observe both the brake pedal feel and travel.
  3. Release the brakes and turn OFF the ignition.
  4. If the brake pedal apply felt spongy, but the brake pedal travel was not excessive, perform the following steps: Inspect the brake system for external leaks. Refer to «Brake System External Leak Inspection»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-system-external-leak-inspection) . Pressure bleed the brake system in order to purge any air that may be trapped in the system. Refer to «Hydraulic Brake System Bleeding (Pressure)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Hydraulic Brake System Bleeding (Manual)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  5. If the brake pedal apply did not feel spongy, but the brake pedal travel was excessive, perform the following steps: Loosen the master cylinder-to-brake power booster mounting nuts. Carefully pull the master cylinder away from the brake power booster just enough to inspect the mounting surface of the master cylinder. Inspect the master cylinder mounting surface at the primary piston (2) for brake fluid leaks.
  6. If the master cylinder exhibits any leakage around the primary piston (2), then the primary piston primary seal (4) and/or secondary seal (3) is leaking and the master cylinder requires overhaul or replacement.
  7. If the master cylinder primary piston (2) does not exhibit any leakage, pressure bleed the brake system. Refer to «Hydraulic Brake System Bleeding (Pressure)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) or «Hydraulic Brake System Bleeding (Manual)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  8. If the brake pedal apply did not feel spongy, and the brake pedal travel was initially steady and not excessive, but then gradually fell, then the master cylinder requires overhaul or replacement due to an internal leak past the secondary piston (1) from the secondary piston primary seal (6) or secondary seal (5).
  9. If the brake pedal apply did not feel spongy, and the brake pedal travel was initially steady and not excessive, then fell slightly, then became steady again, then the brake pressure modulator valve (BPMV) may be leaking internally, and may require replacement.

Hydraulic Brake Component Operation Visual Inspection

  1. With the tire and wheel assemblies removed and the brake rotors retained by wheel lug nuts, visually inspect the caliper piston dust boot (2) sealing area to ensure that there are no brake fluid leaks.
  2. If any evidence of a brake fluid leak is present, the brake caliper requires overhaul or replacement.
  3. While the brake system is at rest (4), observe the position of the caliper piston (1) in relation to the caliper housing.
  4. Have an assistant apply and release the brake pedal several times while you observe the operation of the hydraulic brake caliper. Observe the caliper piston (1) for unrestricted and even movement during each apply of the brake system (5). Observe the caliper piston (1) for an unrestricted and even return motion during each release of the brake system (6).
  5. If the caliper piston (1) did not exhibit unrestricted and even movement during brake system apply and/or release, the piston square seal (3) may be worn or damaged and the caliper may require overhaul or replacement.

Brake Pipe and Hose Inspection

WARNINGRefer to Brake Fluid Irritant Warning .
  1. Visually inspect all of the brake pipes for the following conditions: Kinks, improper routing, missing or damaged retainers Leaking fittings, excessive corrosion
  2. If any of the brake pipes exhibited any of the conditions listed, then the identified pipe, or pipes, require replacement.
  3. Ensure that the vehicle axles are properly supported at ride height in order to maintain the proper relationship of the flexible brake hoses to the chassis.
  4. Visually inspect all of the flexible brake hoses for the following conditions: Kinks (1), improper routing, twists, chafing, missing or damaged retainers Leaking connections, cracking, dry-rot, blisters, bulges
  5. If any of the flexible brake hoses exhibited any of the conditions listed, then the identified flexible brake hose, or hoses require replacement.
  6. Squeeze the flexible brake hoses with firm finger pressure to check for soft spots (2), indicating an internal restriction. Check the entire length of each flexible brake hose.
  7. If any of the flexible brake hoses were found to have soft spots (2), then the identified flexible brake hose, or hoses require replacement.

Brake Pedal Pushrod Inspection

  1. Disconnect the brake pedal pushrod (1) from the brake pedal.
  2. Inspect the brake pedal pushrod eyelet bushing (2), if equipped, for cracks and/or excessive wear.
  3. Reposition the pedal pushrod boot (3) toward the front of the vehicle to expose as much of the pedal pushrod (1) as possible.
  4. Inspect the brake pedal pushrod (1) for straightness.
  5. If the brake pedal pushrod eyelet bushing (2) exhibited cracks and/or excessive wear, then the bushing requires replacement.
  6. If the brake pedal pushrod (1) is not straight, then the pushrod requires replacement.
  7. Return the pedal pushrod boot (3) to its original position on the pedal pushrod (1).
  8. Connect the brake pedal pushrod (1) to the brake pedal.

Master Cylinder Reservoir Filling

WARNINGRefer to Brake Fluid Irritant Warning .
  1. Visually inspect the brake fluid level through the brake master cylinder reservoir.
  2. If the brake fluid level is at or below the half-full point during routine fluid checks, the brake system should be inspected for wear and possible brake fluid leaks.
  3. If the brake fluid level is at or below the half-full point during routine fluid checks, and an inspection of the brake system did not reveal wear or brake fluid leaks, the brake fluid may be topped-off up to the maximum-fill level.
  4. If brake system service was just completed, the brake fluid may be topped-off up to the maximum-fill level.
  5. If the brake fluid level is above the half-full point, adding brake fluid is not recommended under normal conditions.
  6. If brake fluid is to be added to the master cylinder reservoir, clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and diaphragm. Use only GM approved brake fluid from a clean, sealed brake fluid container.

Removal Procedure

WARNINGRefer to Brake Fluid Irritant Warning .
  1. Thoroughly clean the master cylinder reservoir and the master cylinder body to remove any dirt and debris.
  2. Disconnect the brake fluid level indicator switch electrical connector.
  3. Remove and properly dispose of the brake fluid in the master cylinder reservoir.
  4. Remove the master cylinder reservoir (1) by carefully spreading the 4 locking tabs and lifting the master cylinder reservoir upward.
  5. Remove the brake fluid level indicator switch, if necessary. Refer to «Brake Fluid Level Indicator Switch Replacement»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  6. Remove the master cylinder reservoir seals (1). Inspect the seals for damage and replace, if necessary.

Installation Procedure

  1. Lightly lubricate the master cylinder reservoir seals with approved brake fluid from a clean, sealed brake fluid container. Refer to «Fluid and Lubricant Recommendations»(/chevrolet/corvette/c6-2004-2014/remont/lubrication-system/#maintenance-and-lubrication__fluid-and-lubricant-recommendations) .
  2. Install the master cylinder reservoir seals (1). Ensure the seals are fully seated in the master cylinder ports.
  3. Install the brake fluid level indicator switch, if removed. Refer to «Brake Fluid Level Indicator Switch Replacement»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  4. Install the master cylinder reservoir (1) by carefully inserting the reservoir port barrels into the master cylinder and pressing downward. Ensure the 4 locking tabs fully engage the posts on the master cylinder body.
  5. Connect the brake fluid level indicator switch electrical connector.
  6. Fill the master cylinder reservoir. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) .
  1. Place the ignition switch in the OFF position.
  2. Apply and release the brake pedal several times until the pedal becomes firm to deplete the power vacuum brake booster vacuum reserve.
  3. Thoroughly clean the master cylinder reservoir and the master cylinder body to remove any dirt and debris.
  4. Disconnect the brake fluid level indicator switch electrical connector.
  5. Remove and properly dispose of the brake fluid in the master cylinder reservoir.
  6. Disconnect the master cylinder secondary brake pipe fitting (1). Cap the brake pipe fitting and plug the master cylinder outlet port to prevent brake fluid loss and contamination.
  7. Disconnect the master cylinder primary brake pipe fitting (1). Cap the brake pipe fitting and plug the master cylinder outlet port to prevent brake fluid loss and contamination.
  8. Remove the master cylinder nuts (1).
  9. Remove the master cylinder (1) from the power vacuum brake booster.
  10. Remove the brake fluid level indicator switch, if necessary. Refer to «Brake Fluid Level Indicator Switch Replacement»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  11. Remove the master cylinder reservoir, if necessary. Refer to «Master Cylinder Reservoir Replacement»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  1. Install the master cylinder reservoir, if removed. Refer to «Master Cylinder Reservoir Replacement»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  2. Bench bleed the master cylinder. Refer to «Master Cylinder Bench Bleeding»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-bench-bleeding) .
  3. Install the brake fluid level indicator switch, if removed. Refer to «Brake Fluid Level Indicator Switch Replacement»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  4. Install the master cylinder (1) to the power vacuum brake booster.
  5. Install the master cylinder nuts (1) and tighten to 18 N.m (13 lb ft).
  6. Connect the master cylinder primary brake pipe fitting (1) and tighten to 24 N.m (18 lb ft).
  7. Connect the master cylinder secondary brake pipe fitting (1) and tighten to 24 N.m (18 lb ft).
  8. Connect the brake fluid level indicator switch electrical connector.
  9. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Pressure)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) or «Hydraulic Brake System Bleeding (Manual)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .

Master Cylinder Bench Bleeding

  1. Secure the mounting flange of the brake master cylinder in a bench vise so that the rear of the primary piston is accessible.
  2. Remove the master cylinder reservoir cap and diaphragm.
  3. Install suitable fittings to the master cylinder ports that match the type of flare seat required and also provide for hose attachment.
  4. Install transparent hoses to the fittings installed to the master cylinder ports, then route the hoses into the master cylinder reservoir.
  5. Fill the master cylinder reservoir to at least the half-way point with GM approved brake fluid from a clean, sealed brake fluid container. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) .
  6. Ensure that the ends of the transparent hoses running into the master cylinder reservoir are fully submerged in the brake fluid.
  7. Using a smooth, round-ended tool, depress and release the primary piston as far as it will travel, a depth of about 25 mm (1 in), several times. Observe the flow of fluid coming from the ports. As air is bled from the primary and secondary pistons, the effort required to depress the primary piston will increase and the amount of travel will decrease.
  8. Continue to depress and release the primary piston until fluid flows freely from the ports with no evidence of air bubbles.
  9. Remove the transparent hoses from the master cylinder reservoir.
  10. Install the master cylinder reservoir cap and diaphragm.
  11. Remove the fittings with the transparent hoses from the master cylinder ports. Wrap the master cylinder with a clean shop cloth to prevent brake fluid spills.
  12. Remove the master cylinder from the vise.
  1. Disconnect the brake fluid level indicator switch electrical connector.
  2. Carefully compress the brake fluid level indicator switch locking tabs on the inboard side of the master cylinder reservoir.
  3. Remove the brake fluid level indicator switch (1).
  1. Install the brake fluid level indicator switch (1). Ensure the brake fluid level indicator switch locking tabs fully engage the master cylinder reservoir.
  2. Connect the brake fluid level indicator switch electrical connector.
  1. Remove the instrument panel knee bolster trim panel. Refer to «Driver Knee Bolster Panel Replacement»(/chevrolet/corvette/c6-2004-2014/remont/gauges-instrument-panels/#instrument-panel-trim-and-console-trim) .
  2. Disconnect the accelerator pedal position sensor (1) and brake apply sensor (2).
  3. Remove the retainer, washer, brake booster pushrod, and brake pedal pin from the brake pedal.
  4. Reposition the isolation mat by cutting a small slit in the mat.
  5. Remove the brake pedal pivot bolt and nut.
  6. Remove the brake pedal from the mounting bracket.
  1. Lubricate the bushings, pivot bolt, and all friction parts with high temperature silicone brake lubricant.
  2. Install the brake pedal to the mounting bracket.
  3. Install the pivot bolt and nut. Tighten: Tighten the brake pedal pivot nut to 29 N.m (21 lb ft).
  4. Reposition the dash isolation mat.
  5. Install the retainer, washer, brake booster pushrod, and brake pedal pin to the brake pedal. Verify proper engagement of the retainer to the brake pedal pin by rotating the retainer.
  6. Connect the accelerator pedal position sensor (1) and brake apply sensor (2).
  7. Install the instrument panel knee bolster trim panel. Refer to «Driver Knee Bolster Panel Replacement»(/chevrolet/corvette/c6-2004-2014/remont/gauges-instrument-panels/#instrument-panel-trim-and-console-trim) .

Special Tools

J 45405 Pipe Flaring Tool Kit. See Special Tools .

Replacement Procedure

  1. Inspect the section of brake pipe to be replaced.
  2. Release the brake pipe to be replaced from the retainers, as required.
  3. Select an appropriate location to section the brake pipe, if necessary. Allow adequate clearance in order to maneuver the J 45405 . See «Special Tools»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) . Avoid sectioning the brake pipe at bends or mounting points.
  4. Using a string or wire, measure the length of the pipe to be replaced including all pipe bends.
  5. Add to the measurement taken the appropriate additional length required for each flare to be created. Specification: 6.35 mm (0.250 in) for 4.76 mm (3/16 in) diameter pipe NOTE: Ensure that the brake pipe end to be flared is cut at a square, 90 degree angle to the pipe length.
  6. Using the pipe cutter included in the J 45405 , carefully cut the brake pipe squarely to the measured length. See «Special Tools»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  7. Remove the sectioned brake pipe from the vehicle.
  8. Select the appropriate size of brake pipe and tube nuts, as necessary. The brake pipe outside diameter determines brake pipe size.
  9. Strip the nylon coating from the brake pipe ends to be flared, if necessary. Select the appropriate blade on the coating stripping tool included in the J 45405 , by unthreading the blade block from the stripping tool and installing the block with the desired blade facing the tool rollers. See «Special Tools»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) . Specification: 6.35 mm (0.250 in) blade for 4.76 mm (3/16 in) diameter pipe Insert the brake pipe end to be flared into the stripping tool to the depth of the ledge on the tool rollers. While holding the brake pipe firmly against the stripping tool roller ledges, rotate the thumbwheel of the tool until the blade contacts the brake pipe coated surface. NOTE: Do not gouge the metal surface of the brake pipe. Rotate the stripping tool in a clockwise direction, ensuring that the brake pipe end remains against the tool roller ledges. After each successive revolution of the stripping tool, carefully rotate the thumbwheel of the tool clockwise, in order to continue stripping the coating from the brake pipe until the metal pipe surface is exposed. Loosen the thumbwheel of the tool and remove the brake pipe. NOTE: Ensure that all loose remnants of the nylon coating have been removed from the brake pipe. Inspect the stripped end of the brake pipe to ensure that the proper amount of coating has been removed. Specification: 6.35 mm (0.250 in) for 4.76 mm (3/16 in) diameter pipe
  10. Chamfer the inside and outside diameter of the pipe with the de-burring tool included in the J 45405 . See «Special Tools»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  11. Install the tube nuts on the brake pipe, noting their orientation.
  12. Clean the brake pipe and the J 45405 of lubricant, contaminants, and debris. See «Special Tools»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  13. Loosen the die clamping screw of the J 45405 . See «Special Tools»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  14. Select the corresponding die set and install the die halves into the die cage with the full, flat face of one die facing the clamping screw, and the counterbores of both dies facing the forming ram.
  15. Place the flat face of an unused die (1) against the die halves in the clamping cage and hold firmly against the counterbored face of the dies.
  16. Insert the prepared end of the pipe to be flared through the back of the dies until the pipe is seated against the flat surface of the unused die (1).
  17. Remove the unused die (1).
  18. Ensure that the rear of both dies are seated firmly against the enclosed end of the die cage.
  19. Firmly hand tighten the clamping screw (2) against the dies.
  20. Select the appropriate forming mandrel and place into the forming ram.
  21. Rotate the hydraulic fluid control valve clockwise to the closed position.
  22. Rotate the body of the J 45405 until it bottoms against the die cage. See «Special Tools»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  23. While guiding the forming mandrel into the exposed end of pipe to be flared, operate the lever of the J 45405 until the forming mandrel bottoms against the clamping dies. See «Special Tools»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  24. Rotate the hydraulic fluid control valve counterclockwise to the open position to allow the hydraulic forming ram to retract.
  25. Loosen the die clamping screw and remove the dies and pipe.
  26. If necessary, lightly tap the dies until the die halves separate.
  27. Inspect the brake pipe flare for correct shape and diameter (a). Specification: 7.10 mm (0.279 in) +/- 0.18 mm (0.007 in) flare diameter for 4.76 mm (3/16 in) diameter pipe
  28. If necessary, using the removed section of pipe as a template, shape the new pipe with a suitable brake pipe bending tool. NOTE: When installing the pipe, maintain a clearance of 19 mm (3/4 in) from all moving or vibrating components.
  29. Install the pipe to the vehicle with the appropriate brake pipe unions as required.
  30. If previously released, secure the brake pipe to the retainers.
  31. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Pressure)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) or «Hydraulic Brake System Bleeding (Manual)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  32. With the aid of an assistant, inspect the brake pipe flares for leaks by starting the engine and applying the brakes.

Scheme 2

Scheme 2: Front Brake Hose Replacement (JL9, J55)
Scheme 2: Front Brake Hose Replacement (JL9, J55)
CalloutComponent Name
WARNING: Refer to Brake Dust Warning . WARNING: Refer to Brake Fluid Irritant Warning . Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Retaining Clip
2Brake Pipe Fitting CAUTION: Refer to Fastener Caution . Procedure: Cap the brake pipe fitting to prevent brake fluid loss and contamination. Tighten: 18 N.m (13 lb ft)
3Brake Hose Fitting Bolt Tighten: 40 N.m (30 lb ft)
4Brake Hose Fitting Gaskets (Qty: 2) Procedure Plug the brake caliper inlet port to prevent brake fluid loss and contamination. Install new brake hose fitting gaskets.
5Brake Hose Procedure: After the installation is complete, bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding (Pressure) or Hydraulic Brake System Bleeding (Manual) .
WARNING
Refer to Brake Dust Warning .
WARNING
Refer to Brake Fluid Irritant Warning .
CAUTION
Refer to Fastener Caution .

Scheme 3

Scheme 3: Front Brake Hose Replacement (J56)
Scheme 3: Front Brake Hose Replacement (J56)
CalloutComponent Name
WARNING: Refer to Brake Dust Warning . WARNING: Refer to Brake Fluid Irritant Warning . Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Retaining Clip
2Brake Pipe Fitting CAUTION: Refer to Fastener Caution . Procedure: Cap the brake pipe fitting to prevent brake fluid loss and contamination. Tighten: 18 N.m (13 lb ft)
3Brake Hose Fitting Bolt Tighten: 40 N.m (30 lb ft)
4Brake Hose Fitting Gasket (Qty: 2) Tip: Procedure Plug the brake caliper inlet port to prevent brake fluid loss and contamination. Discard the brake hose fitting gaskets. Install new brake hose fitting gaskets.
5Brake Hose Procedure: After the installation is complete, bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding (Pressure) or Hydraulic Brake System Bleeding (Manual) .
WARNING
Refer to Brake Dust Warning .
WARNING
Refer to Brake Fluid Irritant Warning .
CAUTION
Refer to Fastener Caution .
WARNINGRefer to Brake Dust Warning .
WARNINGRefer to Brake Fluid Irritant Warning .
  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/corvette/c6-2004-2014/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) .
  2. Install the disc brake rotor protectors and remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/corvette/c6-2004-2014/remont/wheel-tire-system/#tires-and-wheels) .
  3. Disconnect the brake pipe fitting (1). Cap the brake pipe fitting to prevent brake fluid loss and contamination.
  4. Remove the brake hose bracket bolt (1).
  5. Remove the brake hose fitting bolt (1).
  6. Remove and discard the brake hose fitting gaskets (2).
  7. Remove the brake hose (3).
  1. Assemble the brake hose fitting bolt (1) and 2 new brake hose fitting gaskets (2) to the brake hose (3).
  2. Install the brake hose assembly to the caliper and tighten the brake hose fitting bolt to 40 N.m (30 lb ft).
  3. Install the brake hose bracket bolt (1) and tighten to 10 N.m (89 lb in).
  4. Connect the brake pipe fitting (1) and tighten to 18 N.m (13 lb ft).
  5. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Pressure)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) or «Hydraulic Brake System Bleeding (Manual)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  6. Install the tire and wheel assembly and remove the disc brake rotor protectors. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/corvette/c6-2004-2014/remont/wheel-tire-system/#tires-and-wheels) .

Scheme 4

Scheme 4: Rear Brake Hose Replacement (JL9, J55)
Scheme 4: Rear Brake Hose Replacement (JL9, J55)
CalloutComponent Name
WARNING: Refer to Brake Dust Warning . WARNING: Refer to Brake Fluid Irritant Warning . Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Retaining Clip
2Brake Pipe Fitting CAUTION: Refer to Fastener Caution . Tighten: 18 N.m (13 lb ft) Procedure: Cap the brake pipe fitting to prevent fluid loss and contamination.
3Brake Hose
4Brake Hose Fitting Bolt Tighten: 40 N.m (30 lb ft)
5Brake Hose Fitting Gasket (Qty: 2) Procedure Discard the brake hose fitting gaskets. Install new brake hose fitting gaskets.
6Brake Hose Procedure: After the installation is complete, bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding (Pressure) or Hydraulic Brake System Bleeding (Manual) .
WARNING
Refer to Brake Dust Warning .
WARNING
Refer to Brake Fluid Irritant Warning .
CAUTION
Refer to Fastener Caution .

Scheme 5

Scheme 5: Rear Brake Hose Replacement (J56)
Scheme 5: Rear Brake Hose Replacement (J56)
CalloutComponent Name
WARNING: Refer to Brake Dust Warning . WARNING: Refer to Brake Fluid Irritant Warning . Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .
1Brake Pipe Fitting CAUTION: Refer to Fastener Caution . Procedure: Cap the brake pipe fitting to prevent fluid leakage and contamination. Tighten: 18 N.m (13 lb ft)
2Retaining Clip
3Brake Hose Fitting
4Brake Hose Fitting Bolt Tighten: 40 N.m (30 lb ft)
5Brake Hose Fitting Gasket (Qty: 2) Procedure Discard the brake hose fitting gaskets. Install new brake hose fitting gaskets.
6Brake Hose Procedure: After the installation is complete, bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding (Pressure) or Hydraulic Brake System Bleeding (Manual) .
WARNING
Refer to Brake Dust Warning .
WARNING
Refer to Brake Fluid Irritant Warning .
CAUTION
Refer to Fastener Caution .
WARNINGRefer to Brake Dust Warning .
WARNINGRefer to Brake Fluid Irritant Warning .
  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/corvette/c6-2004-2014/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) .
  2. Install the disc brake rotor protectors and remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/corvette/c6-2004-2014/remont/wheel-tire-system/#tires-and-wheels) .
  3. Remove the brake hose fitting bolt (1).
  4. Remove and discard the brake hose fitting gaskets (2) from the brake hose (3).
  5. Disconnect the brake pipe fitting (1). Cap the brake pipe fitting to prevent brake fluid loss and contamination.
  6. Remove the brake hose bracket bolt (1) and the brake hose.
  1. Install the brake hose and the brake hose bracket bolt (1) and tighten to 10 N.m (89 lb in).
  2. Connect the brake pipe fitting (1) and tighten to 18 N.m (13 lb ft).
  3. Assemble the brake hose fitting bolt (1) and 2 new brake hose fitting gaskets (2) to the brake hose (3).
  4. Install the brake hose assembly to the caliper and tighten the brake hose fitting bolt to 40 N.m (30 lb ft).
  5. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Pressure)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) or «Hydraulic Brake System Bleeding (Manual)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  6. Install the tire and wheel assembly and remove the disc brake rotor protectors. Refer to «Tire and Wheel Removal and Installation»(/chevrolet/corvette/c6-2004-2014/remont/wheel-tire-system/#tires-and-wheels) .
  1. J-29532: Diaphragm Type Brake Pressure Bleeder, or equivalent
  2. J-35589-A: Master Cylinder Bleeder Adapter
WARNINGRefer to Brake Fluid Irritant Warning .

Pressure Bleeding Procedure

  1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills.
  2. With the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort increases significantly, in order to deplete the brake booster power reserve.
  3. If you have performed a brake master cylinder bench bleeding on this vehicle, or if you disconnected the brake pipes from the master cylinder, you must perform the following steps: Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If necessary, add GM approved brake fluid from a clean, sealed brake fluid container. Refer to «Fluid and Lubricant Recommendations»(/chevrolet/corvette/c6-2004-2014/remont/lubrication-system/#maintenance-and-lubrication__fluid-and-lubricant-recommendations) If removal of the reservoir cap and diaphragm is necessary, clean the outside of the reservoir on and around the cap prior to removal. With the rear brake pipe installed securely to the master cylinder, loosen and separate the front brake pipe from the front port of the brake master cylinder. Allow a small amount of brake fluid to gravity bleed from the open port of the master cylinder. Reconnect the brake pipe to the master cylinder port and tighten securely. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the pedal. Loosen the same brake pipe to purge air from the open port of the master cylinder. Tighten the brake pipe, then have the assistant slowly release the brake pedal. Wait 15 seconds, then repeat steps 3.3-3.7 until all air is purged from the same port of the master cylinder. With the front brake pipe installed securely to the master cylinder, after all air has been purged from the front port of the master cylinder, loosen and separate the rear brake pipe from the master cylinder, then repeat steps 3.3-3.8. After completing the final master cylinder port bleeding procedure, ensure that both of the brake pipe-to-master cylinder fittings are properly tightened.
  4. Fill the brake master cylinder reservoir to the maximum-fill level with GM approved brake fluid from a clean, sealed brake fluid container. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) . Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and diaphragm.
  5. Install the J-35589-A: Master Cylinder Bleeder Adapter to the brake master cylinder reservoir.
  6. Check the brake fluid level in the J-29532: Diaphragm Type Brake Pressure Bleeder, or equivalent, or equivalent. Add GM approved brake fluid from a clean, sealed brake fluid container as necessary to bring the level to approximately the half-full point.
  7. Connect the J-29532: Diaphragm Type Brake Pressure Bleeder, or equivalent, or equivalent, to the J-35589-A: Master Cylinder Bleeder Adapter.
  8. Charge the J-29532: Diaphragm Type Brake Pressure Bleeder, or equivalent, or equivalent, air tank to 175-205 kPa (25-30 psi).
  9. Open the J-29532: Diaphragm Type Brake Pressure Bleeder, or equivalent, or equivalent, fluid tank valve to allow pressurized brake fluid to enter the brake system.
  10. Wait approximately 30 seconds, then inspect the entire hydraulic brake system in order to ensure that there are no existing external brake fluid leaks. Any brake fluid leaks identified require repair prior to completing this procedure.
  11. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
  12. Install a transparent hose over the end of the bleeder valve.
  13. Submerge the open end of the transparent hose into a transparent container partially filled with GM approved brake fluid from a clean, sealed brake fluid container.
  14. Loosen the bleeder valve to purge air from the wheel hydraulic circuit. Allow fluid to flow until air bubbles stop flowing from the bleeder, then tighten the bleeder valve.
  15. With the right rear wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the right rear hydraulic circuit, install a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
  16. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.
  17. With the left front wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the left front hydraulic circuit, install a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve.
  18. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.
  19. With the left rear wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the left rear hydraulic circuit, install a proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve
  20. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.
  21. After completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4 wheel hydraulic circuit bleeder valves are properly tightened.
  22. Close the J-29532: Diaphragm Type Brake Pressure Bleeder, or equivalent, or equivalent, fluid tank valve, then disconnect the J-29532: Diaphragm Type Brake Pressure Bleeder, or equivalent, or equivalent, from the J-35589-A: Master Cylinder Bleeder Adapter.
  23. Remove the J-35589-A: Master Cylinder Bleeder Adapter from the brake master cylinder reservoir.
  24. Fill the brake master cylinder reservoir to the maximum-fill level with GM approved brake fluid from a clean, sealed brake fluid container.
  25. Slowly depress and release the brake pedal. Observe the feel of the brake pedal.
  26. If the brake pedal feels spongy, perform the following steps: Inspect the brake system for external leaks. Refer to «Brake System External Leak Inspection»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-system-external-leak-inspection) . Using a scan tool, perform the antilock brake system automated bleeding procedure to remove any air that may have been trapped in the brake pressure modulator valve (BPMV). Refer to «Antilock Brake System Automated Bleed Procedure»(/chevrolet/corvette/c6-2004-2014/remont/anti-locktraction-control/#antilock-brake-system) .
  27. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp remains illuminated.
  28. If the brake system warning lamp remains illuminated, refer to «Symptoms - Hydraulic Brakes»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__symptoms-hydraulic-brakes) .

Manual Bleeding Procedure

WARNINGRefer to Brake Fluid Irritant Warning .
  1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills.
  2. With the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort increases significantly, in order to deplete the brake booster power reserve.
  3. If you have performed a brake master cylinder bench bleeding on this vehicle, or if you disconnected the brake pipes from the master cylinder, you must perform the following steps: Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If necessary, add GM approved brake fluid from a clean, sealed brake fluid container. Refer to «Fluid and Lubricant Recommendations»(/chevrolet/corvette/c6-2004-2014/remont/lubrication-system/#maintenance-and-lubrication__fluid-and-lubricant-recommendations) . If removal of the reservoir cap and diaphragm is necessary, clean the outside of the reservoir on and around the cap prior to removal. With the rear brake pipe installed securely to the master cylinder, loosen and separate the front brake pipe from the front port of the brake master cylinder. Allow a small amount of brake fluid to gravity bleed from the open port of the master cylinder. Reconnect the brake pipe to the master cylinder port and tighten securely. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the pedal. Loosen the same brake pipe to purge air from the open port of the master cylinder. Tighten the brake pipe, then have the assistant slowly release the brake pedal. Wait 15 seconds, then repeat steps 3.3-3.7 until all air is purged from the same port of the master cylinder. With the front brake pipe installed securely to the master cylinder, after all air has been purged from the front port of the master cylinder, loosen and separate the rear brake pipe from the master cylinder, then repeat steps 3.3-3.8. After completing the final master cylinder port bleeding procedure, ensure that both of the brake pipe-to-master cylinder fittings are properly tightened.
  4. Fill the brake master cylinder reservoir with GM approved brake fluid from a clean, sealed brake fluid container. Ensure that the brake master cylinder reservoir remains at least half-full during this bleeding procedure. Add fluid as needed to maintain the proper level. Refer to «Master Cylinder Reservoir Filling»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-reservoir-filling) . Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and diaphragm.
  5. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
  6. Install a transparent hose over the end of the bleeder valve.
  7. Submerge the open end of the transparent hose into a transparent container partially filled with GM approved brake fluid from a clean, sealed brake fluid container.
  8. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the pedal.
  9. Loosen the bleeder valve to purge air from the wheel hydraulic circuit.
  10. Tighten the bleeder valve, then have the assistant slowly release the brake pedal.
  11. Wait 15 seconds, then repeat steps 8-10 until all air is purged from the same wheel hydraulic circuit.
  12. With the right rear wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the right rear hydraulic circuit, install a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
  13. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11.
  14. With the left front wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the left front hydraulic circuit, install a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve.
  15. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11.
  16. With the left rear wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the left rear hydraulic circuit, install a proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve.
  17. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11.
  18. After completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4 wheel hydraulic circuit bleeder valves are properly tightened.
  19. Fill the brake master cylinder reservoir to the maximum-fill level with GM approved brake fluid from a clean, sealed brake fluid container.
  20. Slowly depress and release the brake pedal. Observe the feel of the brake pedal.
  21. If the brake pedal feels spongy, repeat the bleeding procedure again. If the brake pedal still feels spongy after repeating the bleeding procedure, perform the following steps: Inspect the brake system for external leaks. Refer to «Brake System External Leak Inspection»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-system-external-leak-inspection) . Pressure bleed the hydraulic brake system in order to purge any air that may still be trapped in the system.
  22. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp remains illuminated.
  23. If the brake system warning lamp remains illuminated, refer to «Symptoms - Hydraulic Brakes»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system__symptoms-hydraulic-brakes) .
WARNINGRefer to Brake Fluid Irritant Warning .
  1. Inspect the brake fluid for the following conditions, indicating brake fluid contamination: Fluid separation, indicating 2 types of fluid are present; a substance other than the recommended brake fluid has been introduced into the brake hydraulic system Swirled appearance - oil-based substance Layered appearance - silicone-based substance Fluid discoloration, indicating the presence of moisture or particles that have been introduced into the brake hydraulic system Cloudy appearance - moisture Dark appearance/suspended particles in fluid - dirt, rust, corrosion, brake dust
  2. Inspect the master cylinder reservoir cap diaphragm and the reservoir-to-master cylinder grommets for swelling, indicating brake fluid contamination.
  3. If the brake fluid WAS contaminated with an oil-based or a silicone-based substance, indicated by fluid separation and/or a swollen master cylinder reservoir cap diaphragm and/or swollen reservoir-to-master cylinder grommets, perform the following: Remove ALL of the following components listed from the vehicle. Each component contains internal rubber seals/linings which have been contaminated by the contaminated brake fluid in the brake hydraulic system. Refer to the procedures indicated: «Master Cylinder Replacement»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Front Brake Hose Replacement (JL9, J55)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Front Brake Hose Replacement (J56)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Front Brake Hose Replacement (J57)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Rear Brake Hose Replacement (JL9, J55)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Rear Brake Hose Replacement (J56)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Rear Brake Hose Replacement (J57)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Front Brake Caliper Replacement (JL9, J55)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Front Brake Caliper Replacement (J56)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Front Brake Caliper Replacement (J57)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Rear Brake Caliper Replacement (JL9, J55)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Rear Brake Caliper Replacement (J56)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Rear Brake Caliper Replacement (J57)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Brake Pressure Modulator Valve Replacement»(/chevrolet/corvette/c6-2004-2014/remont/anti-locktraction-control/#antilock-brake-system) Clean out all the hydraulic brake pipes using denatured alcohol, or equivalent. Dry the brake pipes using non-lubricated, filtered air. Repair or replace ALL of the following components listed and install them to the vehicle. Each component contains internal rubber seals/linings which have been contaminated by the contaminated brake fluid in the brake hydraulic system. Refer to the procedures indicated: «Master Cylinder Replacement»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) ; also perform the following: Clean the brake master cylinder reservoir using denatured alcohol, or equivalent, then dry the reservoir using non-lubricated, filtered air. Inspect the reservoir for cracks and/or damage and replace if necessary. Refer to «Master Cylinder Reservoir Replacement»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) . Replace the brake master cylinder reservoir cap diaphragm. «Front Brake Hose Replacement (JL9, J55)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Front Brake Hose Replacement (J56)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Front Brake Hose Replacement (J57)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Rear Brake Hose Replacement (JL9, J55)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Rear Brake Hose Replacement (J56)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Rear Brake Hose Replacement (J57)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) «Front Brake Caliper Overhaul (JL9, J55)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system__front-brake-caliper-overhaul-jl9-j55) «Front Brake Caliper Overhaul (J56, J57)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) or «Front Brake Caliper Replacement (JL9, J55)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Front Brake Caliper Replacement (J56)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Front Brake Caliper Replacement (J57)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Rear Brake Caliper Overhaul (JL9, J55)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system__rear-brake-caliper-overhaul-jl9-j55) «Rear Brake Caliper Overhaul (J56, J57)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) or «Rear Brake Caliper Replacement (JL9, J55)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Rear Brake Caliper Replacement (J56)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Rear Brake Caliper Replacement (J57)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#disc-brake-system) «Brake Pressure Modulator Valve Replacement»(/chevrolet/corvette/c6-2004-2014/remont/anti-locktraction-control/#antilock-brake-system)
  4. If the brake fluid was NOT contaminated with an oil-based or a silicone-based substance, but WAS contaminated with water or dirt, rust, corrosion, and/or brake dust, replace the brake master cylinder reservoir cap diaphragm. The diaphragm may have allowed the moisture or particles to enter the hydraulic system.
  5. Fill the brake master cylinder reservoir to the maximum-fill level with approved brake fluid from a clean, sealed brake fluid container as specified in the owners manual.
  6. Pressure bleed the hydraulic brake system. Begin the procedure with the pressure bleeder reservoir filled to the maximum-fill level with the correct brake fluid as indicated. Refer to «Hydraulic Brake System Bleeding (Pressure)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) or «Hydraulic Brake System Bleeding (Manual)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  1. Turn the ignition switch to the OFF position.
  2. Apply and release the brake pedal several times until the pedal becomes firm to deplete the power vacuum brake booster vacuum reserve.
  3. Disconnect the battery negative cable. Refer to «Battery Negative Cable Disconnection and Connection (LS7 or LS9)»(/chevrolet/corvette/c6-2004-2014/remont/charging-system/#battery-charging-system-starting-system) or «Battery Negative Cable Disconnection and Connection (LS3)»(/chevrolet/corvette/c6-2004-2014/remont/charging-system/#battery-charging-system-starting-system) .
  4. Disconnect the brake fluid level indicator switch electrical connector.
  5. Without disconnecting the radiator surge tank inlet and outlet hoses, remove the radiator surge tank and position aside. Refer to «Radiator Surge Tank Replacement»(/chevrolet/corvette/c6-2004-2014/remont/cooling-system-mechanical/#engine-cooling-system) .
  6. Disconnect the vacuum brake booster check valve (1) from the power vacuum brake booster and position aside.
  7. Remove the master cylinder nuts (1).
  8. Without disconnecting the brake pipe fittings, remove the master cylinder and position aside. Secure the master cylinder in an upright position with heavy mechanics wire or equivalent.
  9. Remove the driver knee bolster panel. Refer to «Driver Knee Bolster Panel Replacement»(/chevrolet/corvette/c6-2004-2014/remont/gauges-instrument-panels/#instrument-panel-trim-and-console-trim) .
  10. Remove the brake pedal position sensor. Refer to «Brake Pedal Position Sensor Replacement»(/chevrolet/corvette/c6-2004-2014/remont/exterior-lights/#lighting-systems__brake-pedal-position-sensor-replacement) .
  11. Remove the telescoping steering column motor bracket and position the motor assembly to the right of the steering column. Refer to «Telescope Motor Assembly Replacement»(/chevrolet/corvette/c6-2004-2014/remont/steering-column-switches/#steering-wheel-and-steering-column) .
  12. Remove the brake booster pushrod clevis pin retainer (1).
  13. Remove the brake booster pushrod clevis pin (1).
  14. Remove the power vacuum brake booster nuts (1).
  15. Remove the power vacuum brake booster (1). Move the power vacuum brake booster from side-to-side to release the booster studs from the push-on nuts.
  16. Remove the power vacuum brake booster gasket (2). Inspect the gasket for damage and replace, if necessary.
  1. Install the power vacuum brake booster (1) and the gasket (2) to the vehicle.
  2. Install the power vacuum brake booster nuts (1) and tighten to 27 N.m (20 lb ft).
  3. Install the brake booster pushrod clevis pin (1) to the brake pedal and the power vacuum brake booster pushrod.
  4. Install the brake booster pushrod clevis pin retainer (1). Rotate the clevis pin retainer to ensure it is fully engaged in the clevis pin groove.
  5. Position and install the telescoping steering column motor and bracket assembly to the steering column. Refer to «Telescope Motor Assembly Replacement»(/chevrolet/corvette/c6-2004-2014/remont/steering-column-switches/#steering-wheel-and-steering-column) .
  6. Install the brake pedal position sensor. Refer to «Brake Pedal Position Sensor Replacement»(/chevrolet/corvette/c6-2004-2014/remont/exterior-lights/#lighting-systems__brake-pedal-position-sensor-replacement) .
  7. Install the driver knee bolster panel. Refer to «Driver Knee Bolster Panel Replacement»(/chevrolet/corvette/c6-2004-2014/remont/gauges-instrument-panels/#instrument-panel-trim-and-console-trim) .
  8. Install the master cylinder to the power vacuum brake booster.
  9. Install the master cylinder nuts (1) and tighten to 18 N.m (13 lb ft).
  10. Connect the brake fluid level indicator switch electrical connector.
  11. Connect the vacuum brake booster check valve (1) to the power vacuum brake booster.
  12. Install the radiator surge tank. Refer to «Radiator Surge Tank Replacement»(/chevrolet/corvette/c6-2004-2014/remont/cooling-system-mechanical/#engine-cooling-system) .
  13. Connect the brake fluid level indicator switch electrical connector.
  14. Connect the battery negative cable. Refer to «Battery Negative Cable Disconnection and Connection (LS7 or LS9)»(/chevrolet/corvette/c6-2004-2014/remont/charging-system/#battery-charging-system-starting-system) or «Battery Negative Cable Disconnection and Connection (LS3)»(/chevrolet/corvette/c6-2004-2014/remont/charging-system/#battery-charging-system-starting-system) .
  1. Turn the ignition switch to the OFF position.
  2. Apply and release the brake pedal several times until the pedal becomes firm to deplete the power vacuum brake booster vacuum reserve.
  3. Remove the upper intake manifold sight shield. Refer to «Upper Intake Manifold Sight Shield Replacement (LS9)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical/#engine-mechanical-62l-or-70l-2-of-8) or «Upper Intake Manifold Sight Shield Replacement (w/o LS9)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical/#engine-mechanical-62l-or-70l-2-of-8) .
  4. Disconnect the vacuum brake booster check valve and hose assembly (1) from the power vacuum brake booster.
  5. Disconnect the vacuum brake booster vacuum hose (1) from the engine.
  1. Connect the vacuum brake booster vacuum hose (1) to the engine. A small amount of denatured alcohol may be used as a lubricant to ease installation, if necessary.
  2. Connect the vacuum brake booster check valve and hose assembly (1) to the power vacuum brake booster. A small amount of denatured alcohol may be used as a lubricant to ease installation, if necessary.
  3. Install the upper intake manifold sight shield. Refer to «Upper Intake Manifold Sight Shield Replacement (LS9)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical/#engine-mechanical-62l-or-70l-2-of-8) or «Upper Intake Manifold Sight Shield Replacement (w/o LS9)»(/chevrolet/corvette/c6-2004-2014/remont/mechanical/#engine-mechanical-62l-or-70l-2-of-8) .

Brake Warning Indicator

The instrument panel cluster (IPC) illuminates the brake warning indicator when the following occurs

  1. The IPC detects that the park brake is applied. The park brake switch signal circuit is pulled to ground.
  2. The IPC detects a low brake fluid condition. The brake fluid level sensor signal circuit is pulled to ground for 15 seconds.
  3. The electronic brake control module (EBCM) detects a malfunction with the antilock brake system. The IPC receives a serial data message from the EBCM requesting illumination.
  4. The IPC detects a loss of communications with the EBCM.
  5. The IPC performs the bulb check at the start of each ignition cycle. The indicators illuminate for approximately 5 seconds.
  6. The Display Test is performed with a scan tool.

CHECK BRAKE FLUID Message

The driver information center (DIC) displays the CHECK BRAKE FLUID message when the IPC detects that the brake fluid level is below the normal operating range for 15 seconds.

System Component Description

The hydraulic brake system consists of the following

System Operation

Mechanical force is converted into hydraulic pressure by the master cylinder, regulated to meet braking system demands by the pressure balance control system, and delivered to the hydraulic brake wheel circuits by the pipes and flexible hoses. The wheel apply components then convert the hydraulic pressure back into mechanical force which presses linings against rotating brake system components.

The brake assist system consists of the following

Brake system input force from the driver is multiplied by the brake pedal and transferred by the pedal pushrod to the hydraulic brake master cylinder. Effort required to apply the brake system is reduced by the operation of the vacuum brake booster.

When brake system force is applied, vacuum to the rear of the diaphragm(s) is cut off, and air at atmospheric pressure is admitted in its place. The vacuum acts to pull the diaphragm(s) forward, while the atmospheric pressure acts to push from behind. As a result, the amount of effort required by the driver is reduced. When input force is removed, vacuum again replaces atmospheric pressure within the vacuum power brake booster to help return the booster to rest. Return springs maintain the system in a rest position.

If the vehicle is equipped with a vacuum monitoring system, the powertrain control module(s) typically will alter powertrain functions and/or command the vacuum pump ON, if equipped, to provide for the vacuum needs of the brake assist system, as operating conditions warrant.

Illustration Tool Number/Description J 28662 Brake Pedal Effort Gage J 29532 Diaphragm Pressure Bleeder J 35589-A Master Cylinder Bleeder Adapter J 45405 Pipe Flaring Tool Kit

Scheme 6

Scheme 6: Special Tools
Scheme 6: Special Tools

Scheme 7

Scheme 7
Scheme 7

Scheme 8

Scheme 8
Scheme 8

Scheme 9

Scheme 9
Scheme 9

See also:
• Diagnostic System Check - Vehicle
• Strategy Based Diagnosis
• Diagnostic Procedure Instructions
• Component Connector End Views
• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Control Module References
• Diagnostic Repair Verification
• Disc Brake System Description and Operation
• Checking Aftermarket Accessories
• Parking Brake Indicator Switch Replacement
• Park Brake System Diagnosis
• Diagnostic Starting Point - Suspension General Diagnosis
• Diagnostic Starting Point - Power Steering System (w/o Electro-Hydraulic Steering)
• Brake Pad Inspection (JL9, J55, J56)
• Brake Pad Inspection (J57)
• Front Disc Brake Mounting and Hardware Inspection
• Rear Disc Brake Mounting and Hardware Inspection
• Front Brake Caliper Overhaul (JL9, J55)
• Rear Brake Caliper Overhaul (JL9, J55)
• Wheel Drive Shaft Outer Joint and Boot Replacement
• Brake Rotor Thickness Variation Measurement (JL9, J55, J56)
• Brake Rotor Thickness Variation Measurement (J57)
• Brake Rotor Surface and Wear Inspection (JL9, J55, J56)
• Brake Rotor Assembled Lateral Runout Correction
• Brake Pressure Modulator Valve Replacement
• Lifting and Jacking the Vehicle
• Tire and Wheel Removal and Installation
• Brake Fluid Irritant Warning
• Brake Fluid Effects on Paint and Electrical Components Caution
• Fluid and Lubricant Recommendations
• Fastener Caution
• Driver Knee Bolster Panel Replacement
• Brake Dust Warning
• Battery Negative Cable Disconnection and Connection (LS7 or LS9)
• Radiator Surge Tank Replacement
• Brake Pedal Position Sensor Replacement
• Telescope Motor Assembly Replacement
• Upper Intake Manifold Sight Shield Replacement (LS9)
• ABS Description and Operation
• DTC C0267
• Brake Fluid Loss
• Brake Pulsation
• Brake System Noise
• Brake Pedal Excessive Travel
• Brake Pedal Excessive Effort
• Brakes Drag
• Brake System Slow Release
• Park Brake Switch Malfunction
• Brake Fluid Level Switch Malfunction
• Diagnostic Starting Point - Hydraulic Brakes
• Brake Assist System Diagnosis
• Brake Pedal Pushrod Inspection
• Master Cylinder Reservoir Filling
• Hydraulic Brake Component Operation Visual Inspection
• Brake Pipe and Hose Inspection
• Brake System Internal Leak Test
• Brake System Vacuum Source Test
• Symptoms - Hydraulic Brakes
• Brake System External Leak Inspection
• Master Cylinder Bench Bleeding

More articles — Brakes