Hydraulic Brake System Buick Encore I

Fastener Tightening Specifications

Fastener Tightening Specifications

Brake Component Specifications

Brake Component Specifications

Brake System Specifications

Brake System Specifications

Scheme 1

Scheme 2

Diagnostic Code Index

DIAGNOSTIC CODE INDEX

Diagnostic Instructions

1. Perform the «Diagnostic System Check - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

DTC Descriptor

For symptom byte information refer to Symptom Byte List .

Diagnostic Fault Information

Circuit/System Description

The brake fluid level switch monitors the level of the brake fluid in the brake fluid reservoir. When the electronic brake control module sees low brake fluid level, the DTC is set.

Conditions for Running the DTC

Ignition ON.

Conditions for Setting the DTC

Low brake fluid level is detected for 8 s.

Action Taken When the DTC Sets

1. The electronic brake control module disables the traction control and stability control for the duration of the ignition cycle.
2. The traction control/stability control-active indicator turns ON.
3. The brake warning indicator turns ON.

Conditions for Clearing the DTC

The condition for setting the DTC is no longer present.

Reference Information

Schematic Reference

Hydraulic Brake Schematics (Encore) , Hydraulic Brake Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Brake Warning System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Verify that the brake is above minimum level. If low Refer to «Brake Fluid Loss»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-fluid-loss) . If above minimum level
2. Ignition ON.
3. Verify the scan tool Brake Fluid Level Sensor parameter is Ok. If the parameter is Low Refer to Circuit/System Testing. If the parameter is Ok
4. All OK.

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B20 Brake Fluid Level Switch. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 2 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Ignition ON.
4. Verify the scan tool Brake Fluid Level Sensor parameter is Low. If the parameter is not Low Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module. Test for infinite resistance between the signal circuit terminal 1 and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the K17 Electronic Brake Control Module. If the parameter is Low
5. Install a 3 A fused jumper wire between the signal circuit terminal 1 and ground.
6. Verify the scan tool Brake Fluid Level Sensor parameter is Ok. If the parameter is not Ok Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module, ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V. Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K17 Electronic Brake Control Module. If the parameter is Ok
7. Test or replace the B20 Brake Fluid Level Switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

1. «Brake Fluid Level Indicator Switch Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system)
2. «Control Module References»(/buick/encore/i-2012-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for electronic brake control module replacement, programming and setup.

1. Perform the «Diagnostic System Check - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

DTC Descriptors

For symptom byte information refer to Symptom Byte List .

The brake booster vacuum sensor measures the vacuum in the brake booster. The electronic brake control module supplies a 5 v reference and a low reference circuit to the brake booster vacuum sensor. The vacuum sensor supplies a voltage signal in relation to the pressure in the brake booster to the electronic brake control module. When the vacuum within the system becomes low, the electronic brake control module turns on the brake booster pump motor by providing battery voltage to the brake booster pump motor relay. The relay activates and supplies the voltage to the brake booster pump motor.

Engine running

C025E 01

1. A short to voltage is detected on the signal circuit.
2. A short to voltage is detected on the 5 V reference circuit.
3. A short to voltage is detected on the relay control circuit.

C025E 04

1. A open/high resistance is detected on the vacuum sensor signal circuit.
2. A open/high resistance is detected on the relay control circuit.

C025E 5A

The Electronic Brake Control Module detected an erratic Vacuum Sensor Signal that is not plausible.

C025E 71

The electronic brake control module receives an invalid serial data message from the engine control module.

C027B 01

The electronic brake control module receives an invalid serial data message from the engine control module.

C027B 04

The electronic brake control module receives an invalid serial data message from the engine control module.

1. The ABS indicator turns ON.
2. The red Brake warning indicator turns ON.
3. The Electronic Brake Control Module disables the ABS, the traction control, and the electronic stability control for the duration of the ignition cycle.

1. A current DTC clears when the diagnostic runs and passes.
2. The history DTC will clear after 40 consecutive fault-free ignition cycles have occurred.

Schematic Reference

Hydraulic Brake Schematics (Encore) , Hydraulic Brake Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Brake Assist System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

C025E 71

1. Ignition ON.
2. Verify that no other DTCs are set. If any other DTCs are set Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) . If no other DTCs are set
3. Replace the K20 Engine Control Module.
4. Verify the DTC C025E does not set while operating the vehicle under the conditions for Running the DTC. If the DTC sets Replace the K17 Electronic Brake Control Module. If the DTC does not set
5. All OK.

C025E 01, C025E 04, C025E 5A, C027B 01, or C027B 04

1. Ignition OFF and all vehicle systems OFF, disconnect the KR14 Brake Booster Pump Motor Relay. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 1 (86) and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Ignition ON.
4. Verify a test lamp illuminates between the B+ circuit terminal 3 (30) and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse. If the test lamp does not illuminate and the circuit fuse is open Ignition OFF. Test for infinite resistance between the B+ circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for infinite resistance between the control circuit terminal 5 (87) and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the KR14 Brake Booster Pump Motor Relay. If the test lamp illuminates
5. Connect a test lamp between the control circuit terminal 2 (85) and the ground circuit terminal 1 (86). Clear EBCM DTCs.
6. Verify the test lamp turns ON and OFF when commanding the Brake Booster Electric Vacuum Pump ON and OFF with a scan tool. If the test lamp is always OFF Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K17 Electronic Brake Control Module. If the test lamp is always ON Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module, ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K17 Electronic Brake Control Module. If the test lamp turns ON and OFF
7. Verify that a test lamp does not illuminate between the control circuit terminal 5 (87) and ground. If the test lamp illuminates Repair the short to voltage on the control circuit If the test lamp does not illuminate
8. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the M9 Brake Booster Pump Motor. It may take up to 2 min for all vehicle systems to power down.
9. Test for less than 10 ohms between the M9 Brake Booster Pump Motor ground circuit terminal 2 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
10. Connect the harness connector at the M9 Brake Booster Pump Motor.
11. Ignition ON, connect a 30 A fused jumper wire between the B+ circuit terminal 3 (30) and the control circuit terminal 5 (87) .
12. Verify the M9 Brake Booster Pump Motor is activated. If the M9 Brake Booster Pump Motor does not activate Ignition OFF, disconnect the harness connector at the M9 Brake Booster Pump Motor. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the M9 Brake Booster Pump Motor. If the M9 Brake Booster Pump Motor activates
13. Test for 60-180 ohms between terminals 85 and 86 on the relay. If less than 60 or greater than 180 ohms Replace the relay. If between 60-180 ohms
14. Test for infinite resistance between the terminals listed below: 30 and 86 30 and 85 30 and 87 85 and 87 If less than infinite resistance Replace the relay. If infinite resistance
15. Install a 20 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground.
16. Test for less than 2 ohms between terminals 30 and 87. If 2 ohms or greater Replace the relay. If less than 2 ohms
17. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B19B Brake Booster Vacuum Sensor. It may take up to 2 min for all vehicle systems to power down.
18. Test for less than 10 ohms between the low reference circuit terminal 2 and ground. If 10 ohms or greater Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module. Test for less than 2 ohms in the low reference circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K17 Electronic Brake Control Module. If less than 10 ohms
19. Ignition ON.
20. Test for 4.8-5.2 V between the 5 V reference circuit terminal 3 and ground. If less than 4.8 V Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module. Test for infinite resistance between the 5 V reference circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the 5 V reference circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K17 Electronic Brake Control Module. If greater than 5.2 V Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module, ignition ON. Test for less than 1 V between the 5 V reference circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K17 Electronic Brake Control Module. If between 4.8-5.2 V
21. Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module, Ignition ON.
22. Test for less than 1 V between the B19B Brake Booster Vacuum Sensor signal circuit terminal 1 and ground. If greater than 1 V Repair the short to voltage on the circuit. If less than 1 V
23. Ignition OFF.
24. Test for infinite resistance between the B19B Brake Booster Vacuum Sensor signal circuit terminal 1 and ground. If less than infinite resistance Repair the short to ground on the circuit. If infinite resistance
25. Test for less than 2 ohms in the B19B Brake Booster Vacuum Sensor signal circuit end to end. If 2 ohms or greater Repair the open/high resistance in the circuit. If less than 2 ohms
26. Replace the B19B Brake Booster Vacuum Sensor.
27. Verify the DTC does not set while operating the vehicle under Conditions for Running the DTC. If the DTC sets Replace the K17 Electronic Brake Control Module. If the DTC does not set
28. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Power Brake Booster Vacuum Hose Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) for brake booster vacuum sensor replacement
2. «Control Module References»(/buick/encore/i-2012-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for control module replacement, programming and setup.

1. Perform the «Diagnostic System Check - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

For symptom byte information refer to Symptom Byte List .

The brake booster vacuum sensor measures the vacuum in the brake booster. The electronic brake control module supplies a 5 v reference and a low reference circuit to the brake booster vacuum sensor. The vacuum sensor supplies a voltage signal in relation to the pressure in the brake booster to the electronic brake control module. When the vacuum within the system becomes low, the electronic brake control module turns on the brake booster pump motor by providing battery voltage to the brake booster pump motor relay. The relay activates and supplies the voltage to the brake booster pump motor.

Engine running

C025E 01

1. A short to voltage is detected on the signal circuit.
2. A short to voltage is detected on the 5 V reference circuit.
3. A short to voltage is detected on the relay control circuit.

C025E 04

1. A open/high resistance is detected on the vacuum sensor signal circuit.
2. A open/high resistance is detected on the relay control circuit.

C025E 5A

The Electronic Brake Control Module detected an erratic Vacuum Sensor Signal that is not plausible.

C025E 71

The electronic brake control module receives an invalid serial data message from the engine control module.

C027B 01

The electronic brake control module receives an invalid serial data message from the engine control module.

C027B 04

The electronic brake control module receives an invalid serial data message from the engine control module.

1. The ABS indicator turns ON.
2. The red Brake warning indicator turns ON.
3. The Electronic Brake Control Module disables the ABS, the traction control, and the electronic stability control for the duration of the ignition cycle.

1. A current DTC clears when the diagnostic runs and passes.
2. The history DTC will clear after 40 consecutive fault-free ignition cycles have occurred.

Schematic Reference

Hydraulic Brake Schematics (Encore) , Hydraulic Brake Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Brake Assist System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

C025E 71

1. Ignition ON.
2. Verify that no other DTCs are set. If any other DTCs are set Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) . If no other DTCs are set
3. Replace the K20 Engine Control Module.
4. Verify the DTC C025E does not set while operating the vehicle under the conditions for Running the DTC. If the DTC sets Replace the K17 Electronic Brake Control Module. If the DTC does not set
5. All OK.

C025E 01, C025E 04, C025E 5A, C027B 01, or C027B 04

1. Ignition OFF and all vehicle systems OFF, disconnect the KR14 Brake Booster Pump Motor Relay. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 1 (86) and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Ignition ON.
4. Verify a test lamp illuminates between the B+ circuit terminal 3 (30) and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse. If the test lamp does not illuminate and the circuit fuse is open Ignition OFF. Test for infinite resistance between the B+ circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for infinite resistance between the control circuit terminal 5 (87) and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the KR14 Brake Booster Pump Motor Relay. If the test lamp illuminates
5. Connect a test lamp between the control circuit terminal 2 (85) and the ground circuit terminal 1 (86). Clear EBCM DTCs.
6. Verify the test lamp turns ON and OFF when commanding the Brake Booster Electric Vacuum Pump ON and OFF with a scan tool. If the test lamp is always OFF Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K17 Electronic Brake Control Module. If the test lamp is always ON Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module, ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K17 Electronic Brake Control Module. If the test lamp turns ON and OFF
7. Verify that a test lamp does not illuminate between the control circuit terminal 5 (87) and ground. If the test lamp illuminates Repair the short to voltage on the control circuit If the test lamp does not illuminate
8. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the M9 Brake Booster Pump Motor. It may take up to 2 min for all vehicle systems to power down.
9. Test for less than 10 ohms between the M9 Brake Booster Pump Motor ground circuit terminal 2 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
10. Connect the harness connector at the M9 Brake Booster Pump Motor.
11. Ignition ON, connect a 30 A fused jumper wire between the B+ circuit terminal 3 (30) and the control circuit terminal 5 (87) .
12. Verify the M9 Brake Booster Pump Motor is activated. If the M9 Brake Booster Pump Motor does not activate Ignition OFF, disconnect the harness connector at the M9 Brake Booster Pump Motor. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the M9 Brake Booster Pump Motor. If the M9 Brake Booster Pump Motor activates
13. Test for 60-180 ohms between terminals 85 and 86 on the relay. If less than 60 or greater than 180 ohms Replace the relay. If between 60-180 ohms
14. Test for infinite resistance between the terminals listed below: 30 and 86 30 and 85 30 and 87 85 and 87 If less than infinite resistance Replace the relay. If infinite resistance
15. Install a 20 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground.
16. Test for less than 2 ohms between terminals 30 and 87. If 2 ohms or greater Replace the relay. If less than 2 ohms
17. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B19B Brake Booster Vacuum Sensor. It may take up to 2 min for all vehicle systems to power down.
18. Test for less than 10 ohms between the low reference circuit terminal 2 and ground. If 10 ohms or greater Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module. Test for less than 2 ohms in the low reference circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K17 Electronic Brake Control Module. If less than 10 ohms
19. Ignition ON.
20. Test for 4.8-5.2 V between the 5 V reference circuit terminal 3 and ground. If less than 4.8 V Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module. Test for infinite resistance between the 5 V reference circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the 5 V reference circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K17 Electronic Brake Control Module. If greater than 5.2 V Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module, ignition ON. Test for less than 1 V between the 5 V reference circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K17 Electronic Brake Control Module. If between 4.8-5.2 V
21. Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module, Ignition ON.
22. Test for less than 1 V between the B19B Brake Booster Vacuum Sensor signal circuit terminal 1 and ground. If greater than 1 V Repair the short to voltage on the circuit. If less than 1 V
23. Ignition OFF.
24. Test for infinite resistance between the B19B Brake Booster Vacuum Sensor signal circuit terminal 1 and ground. If less than infinite resistance Repair the short to ground on the circuit. If infinite resistance
25. Test for less than 2 ohms in the B19B Brake Booster Vacuum Sensor signal circuit end to end. If 2 ohms or greater Repair the open/high resistance in the circuit. If less than 2 ohms
26. Replace the B19B Brake Booster Vacuum Sensor.
27. Verify the DTC does not set while operating the vehicle under Conditions for Running the DTC. If the DTC sets Replace the K17 Electronic Brake Control Module. If the DTC does not set
28. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Power Brake Booster Vacuum Hose Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) for brake booster vacuum sensor replacement
2. «Control Module References»(/buick/encore/i-2012-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for control module replacement, programming and setup.

Symptoms - Hydraulic Brakes

Note. The following steps must be completed before using the symptom tables.

1. Perform the «Brake System Vehicle Road Test»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) before using the hydraulic brake symptom tables in order to duplicate the customers concern.
2. Review the system operation in order to familiarize yourself with the system functions. Refer to the following: «Brake Warning System Description and Operation»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) «Hydraulic Brake System Description and Operation»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) «Brake Booster Vacuum Assist Description and Operation»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) «Brake Assist System Description and Operation»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) «ABS Description and Operation»(/buick/encore/i-2012-2016/remont/anti-locktraction-control/#antilock-brake-system)

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the hydraulic brake system. Refer to «Checking Aftermarket Accessories»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__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 Booster Pump Motor Malfunction (Without J41)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Brake Booster Pump Motor Malfunction (With J41)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system)
2. «Brake Warning Indicator Malfunction (Without J41)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Brake Warning Indicator Malfunction (With J41)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system)
3. «Brake Pulsation»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-pulsation)
4. «Brake System Noise»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-system-noise)
5. «Braking Action Uneven - Pulls to One Side»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system)
6. «Braking Action Uneven - Front to Rear»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system)
7. «Brake Pedal Excessive Travel»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-pedal-excessive-travel)
8. «Brake Pedal Excessive Effort»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-pedal-excessive-effort)
9. «Brakes Drag»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brakes-drag)
10. «Brake System Slow Release»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-system-slow-release)
11. «Brake Fluid Loss»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-fluid-loss)

1. Perform the «Diagnostic System Check - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The brake booster vacuum sensor measures the vacuum in the brake booster. The electronic brake control module supplies a 5 v reference and a low reference circuit to the brake booster vacuum sensor. The vacuum sensor supplies a voltage signal in relation to the pressure in the brake booster to the electronic brake control module. When the vacuum within the system becomes low, the electronic brake control module turns on the brake booster pump motor by providing battery voltage to the brake booster pump motor relay. The relay activates and supplies the voltage to the brake booster pump motor.

Schematic Reference

Hydraulic Brake Schematics (Encore) , Hydraulic Brake Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Brake Booster Vacuum Assist Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References

1. Ignition ON.
2. Verify the M9 Brake Booster Pump Motor turns ON and OFF when commanding the Brake Booster Electric Vacuum Pump ON and OFF with a scan tool. If the M9 Brake Booster Pump Motor does not turn ON and OFF Refer to Circuit/System Testing. If the M9 Brake Booster Pump Motor turn ON and OFF
3. Verify that the brake booster vacuum system has no damage, leakage or incorrect installation. If damage, leakage or incorrect installation is found Refer to «Brake Assist System Diagnosis»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-assist-system-diagnosis) . If the inspection is OK
4. All OK.

1. Ignition OFF and all vehicle systems OFF, disconnect the KR14 Brake Booster Pump Motor Relay. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 1 (86) and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Ignition ON.
4. Verify a test lamp illuminates between the B+ circuit terminal 3 (30) and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse. If the test lamp does not illuminate and the circuit fuse is open Ignition OFF. Test for infinite resistance between the B+ circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for infinite resistance between the control circuit terminal 5 (87) and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the KR14 Brake Booster Pump Motor Relay. If the test lamp illuminates
5. Connect a test lamp between the control circuit terminal 2 (85) and the ground circuit terminal 1 (86).
6. Verify the test lamp turns ON and OFF when commanding the Brake Booster Electric Vacuum Pump ON and OFF with a scan tool. If the test lamp is always OFF Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K17 Electronic Brake Control Module. If the test lamp is always ON Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module, ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K17 Electronic Brake Control Module. If the test lamp turns ON and OFF
7. Verify that a test lamp does not illuminate between the control circuit terminal 5 (87) and ground. If the test lamp illuminates Repair the short to voltage on the control circuit If the test lamp does not illuminate
8. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the M9 Brake Booster Pump Motor. It may take up to 2 min for all vehicle systems to power down.
9. Test for less than 10 ohms between the M9 Brake Booster Pump Motor ground circuit terminal 2 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
10. Connect the harness connector at the M9 Brake Booster Pump Motor.
11. Ignition ON, connect a 30 A fused jumper wire between the B+ circuit terminal 3 (30) and the control circuit terminal 5 (87).
12. Verify the M9 Brake Booster Pump Motor is activated. If the M9 Brake Booster Pump Motor does not activate Ignition OFF, disconnect the harness connector at the M9 Brake Booster Pump Motor. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the M9 Brake Booster Pump Motor. If the M9 Brake Booster Pump Motor activates
13. Test or replace the KR14 Brake Booster Pump Motor Relay.

Component Testing

Motor Test

1. Ignition OFF, disconnect the harness connector at the M9 Brake Booster Pump Motor. Install a 30 A fused jumper wire between the B+ circuit terminal 1 and B+. Install a jumper wire between the ground circuit terminal 2 and ground.
2. Verify the M9 Brake Booster Pump Motor activates. If the brake booster pump motor does not activate Replace the M9 Brake Booster Pump Motor. If the brake booster pump motor activates
3. All OK.

Relay Test

1. Ignition OFF, disconnect the KR14 Brake Booster Pump Motor Relay.
2. Test for 60-180 ohms between terminals 1 and 2. If less than 60 or greater than 180 ohms Replace the relay. If between 60-180 ohms
3. Test for infinite resistance between the terminals listed below: 30 and 86 30 and 85 30 and 87 85 and 87 If less than infinite resistance Replace the relay. If infinite resistance
4. Install a 20 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground.
5. Test for less than 2 ohms between terminals 30 and 87. If 2 ohms or greater Replace the relay. If less than 2 ohms
6. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Relay Replacement (Within an Electrical Center)»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions__relay-replacement-within-an-electrical-center) , «Relay Replacement (Attached to Wire Harness)»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions) .
2. «Power Brake Booster Pump Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
3. «Control Module References»(/buick/encore/i-2012-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for Electronic Brake Control Module replacement, programming and setup.

1. Perform the «Diagnostic System Check - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When the vacuum within the brake booster system becomes low, the brake booster vacuum switch closes and turns on the brake booster pump motor by providing battery voltage to the brake booster pump motor relay. The relay activates and supplies the voltage to the brake booster pump motor.

Schematic Reference

Hydraulic Brake Schematics (Encore) , Hydraulic Brake Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Brake Booster Vacuum Assist Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References

1. Ignition ON.
2. Deplete the vacuum in the brake booster and verify the M9 Brake Booster Pump Motor turns ON If the M9 Brake Booster Pump Motor does not turn ON Refer to Circuit/System Testing. If the M9 Brake Booster Pump Motor turns ON
3. Verify that the brake booster vacuum system has no damage, leakage or incorrect installation. If damage, leakage or incorrect installation is found Refer to «Brake Assist System Diagnosis»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-assist-system-diagnosis) . If the inspection is OK
4. All OK.

1. Ignition OFF and all vehicle systems OFF, disconnect the KR14 Brake Booster Pump Motor Relay. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 1 (86) and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Ignition ON.
4. Verify a test lamp illuminates between the B+ circuit terminal 3 (30) and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF. Test for less than 2 ohms in the B+ circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse. If the test lamp does not illuminate and the circuit fuse is open Ignition OFF. Test for infinite resistance between the B+ circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Disconnect the M9 Brake Booster Pump Motor. Test for infinite resistance between the control circuit terminal 5 (87) and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the KR14 Brake Booster Pump Motor Relay. If the test lamp illuminates
5. Ignition OFF, disconnect the B19C Brake Booster Vacuum Switch, ignition ON.
6. Verify a test lamp illuminates between ignition circuit terminal 1 and ground. If the test lamp does not illuminate and the circuit fuse is good Ignition OFF. Test for less than 2 ohms in the ignition circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse. If the test lamp does not illuminate and the circuit fuse is open Ignition OFF. Test for infinite resistance between the ignition circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance Test for infinite resistance between the B19C Brake Booster Vacuum Switch terminal 2 and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the KR14 Brake Booster Pump Motor Relay. If the test lamp illuminates
7. Connect a test lamp between the KR14 Brake Booster Pump Motor Relay control circuit terminal 2 (85) and the ground circuit terminal 1 (86). If the test lamp illuminates Repair the short to voltage on the control circuit If the test lamp does not illuminate
8. Ignition OFF, connect the B19C Brake Booster Vacuum Switch. Remove the vacuum hose from the brake booster to deplete the vacuum in the system, ignition ON. Verify the test lamp illuminates If the test lamp does not illuminate Ignition OFF, disconnect the harness connector at the B19C Brake Booster Vacuum Switch. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the B19C Brake Booster Vacuum Switch. If the test lamp illuminates
9. Verify that a test lamp does not illuminate between the relay control circuit terminal 5 (87) and ground. If the test lamp illuminates Repair the short to voltage on the control circuit If the test lamp does not illuminate
10. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the M9 Brake Booster Pump Motor. It may take up to 2 min for all vehicle systems to power down.
11. Test for less than 10 ohms between the M9 Brake Booster Pump Motor ground circuit terminal 2 and ground. If 10 ohms or greater Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
12. Connect the harness connector at the M9 Brake Booster Pump Motor.
13. Ignition ON, connect a 30 A fused jumper wire between the B+ circuit terminal 3 (30) and the control circuit terminal 5 (87).
14. Verify the M9 Brake Booster Pump Motor is activated. If the M9 Brake Booster Pump Motor does not activate Ignition OFF, disconnect the harness connector at the M9 Brake Booster Pump Motor. Test for less than 2 ohms in the control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the M9 Brake Booster Pump Motor. If the M9 Brake Booster Pump Motor activates
15. Test or replace the KR14 Brake Booster Pump Motor Relay.

Motor Test

1. Ignition OFF, disconnect the harness connector at the M9 Brake Booster Pump Motor. Install a 30 A fused jumper wire between the B+ circuit terminal 1 and B+. Install a jumper wire between the ground circuit terminal 2 and ground.
2. Verify the M9 Brake Booster Pump Motor activates. If the brake booster pump motor does not activate Replace the M9 Brake Booster Pump Motor. If the brake booster pump motor activates
3. All OK.

Relay Test

1. Ignition OFF, disconnect the KR14 Brake Booster Pump Motor Relay.
2. Test for 60-180 ohms between terminals 1 and 2. If less than 60 or greater than 180 ohms Replace the relay. If between 60-180 ohms
3. Test for infinite resistance between the terminals listed below: 30 and 86 30 and 85 30 and 87 85 and 87 If less than infinite resistance Replace the relay. If infinite resistance
4. Install a 20 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground.
5. Test for less than 2 ohms between terminals 30 and 87. If 2 ohms or greater Replace the relay. If less than 2 ohms
6. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Relay Replacement (Within an Electrical Center)»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions__relay-replacement-within-an-electrical-center) , «Relay Replacement (Attached to Wire Harness)»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-repair-instructions) .
2. «Power Brake Booster Pump Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

1. Perform the «Diagnostic System Check - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The instrument cluster turns ON the brake warning indicator for 5 s after ignition ON. The body control module monitors the parking brake switch and will request the instrument cluster via serial data to turn the brake warning indicator ON when the parking brake is applied. The electronic brake control module monitors the brake fluid level switch and will request the instrument cluster via serial data to turn the brake warning indicator ON when low brake fluid is detected.

Schematic Reference

Hydraulic Brake Schematics (Encore) , Hydraulic Brake Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Hydraulic Brake System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Verify that the brake fluid is above minimum level. If low Refer to «Brake Fluid Loss»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-fluid-loss) . If above minimum level
2. Ignition ON.
3. Verify the scan tool Brake Fluid Level Sensor is OK. If the parameter is Low Refer to Circuit/System Testing - Brake Fluid Level Switch Malfunction. If the parameter is OK
4. Verify the scan tool Park Brake Switch parameter changes between Applied and Released while applying and releasing the parking brake. If the parameter does not change Refer to Circuit/System Testing - Park Brake Switch Malfunction. If the parameter changes
5. Verify the brake warning indicator turns ON and OFF, when commanding the instrument cluster All Indicators On and Off with a scan tool. If the brake warning indicator does not turn ON and OFF Replace the P16 Instrument Cluster. If the brake warning indicator turns ON and OFF
6. All OK.

Note. Circuit/System Verification must be performed before Circuit/System Testing.

Brake Fluid Level Switch Malfunction

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B20 Brake Fluid Level Switch. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 2 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Ignition ON.
4. Verify the scan tool Brake Fluid Level Sensor parameter is Low. If the parameter is not Low Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module. Test for infinite resistance between the signal circuit terminal 1 and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the K17 Electronic Brake Control Module. If the parameter is Low
5. Install a 3 A fused jumper wire between the signal circuit terminal 1 and ground.
6. Verify the scan tool Brake Fluid Level Sensor parameter is OK. If the parameter is Low Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module, ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V. Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K17 Electronic Brake Control Module. If the parameter is OK
7. Test or replace the B20 Brake Fluid Level Switch.

Park Brake Switch Malfunction

1. Ignition OFF, disconnect the harness connector at the B80 Park Brake Switch.
2. Verify that the B80 Park Brake Switch has no physical damage or incorrect installation. If physical damage or incorrect installation is found Test or replace the B80 Park Brake Switch. If the inspection is OK
3. Ignition ON.
4. Verify the scan tool Park Brake Switch parameter is Released. If the parameter is Applied Ignition OFF, disconnect the harness connector at the K9 Body Control Module. Test for infinite resistance between the signal circuit terminal A and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the K9 Body Control Module. If the parameter is Released
5. Install a 3 A fused jumper wire between the signal circuit terminal A and ground.
6. Verify the scan tool Park Brake Switch parameter is Applied. If the parameter is Released Ignition OFF, disconnect the harness connector at the K9 Body Control Module, ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V. Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K9 Body Control Module. If the parameter is Applied
7. Test or replace the B80 Park Brake Switch.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Brake Fluid Level Indicator Switch Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system)
2. «Parking Brake Indicator Switch Replacement»(/buick/encore/i-2012-2016/remont/parking-brake-system/#parking-brake-system)
3. «Control Module References»(/buick/encore/i-2012-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for control module replacement, programming and setup.

1. Perform the «Diagnostic System Check - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The instrument cluster turns ON the brake warning indicator for 5 s after ignition ON. The body control module monitors the parking brake switch and the brake fluid level switch and will request the instrument cluster via serial data to turn the brake warning indicator ON when the parking brake is applied or low brake fluid is detected.

Schematic Reference

Hydraulic Brake Schematics (Encore) , Hydraulic Brake Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Description and Operation

Hydraulic Brake System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Verify that the brake fluid is above minimum level. If low Refer to «Brake Fluid Loss»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-fluid-loss) . If above minimum level
2. Ignition ON.
3. Verify the scan tool Brake Fluid Level Sensor is OK. If the parameter is Low Refer to Circuit/System Testing - Brake Fluid Level Switch Malfunction. If the parameter is OK
4. Verify the scan tool Park Brake Switch parameter changes between Applied and Released while applying and releasing the parking brake. If the parameter does not change Refer to Circuit/System Testing - Park Brake Switch Malfunction. If the parameter changes
5. Verify the brake warning indicator turns ON and OFF, when commanding the instrument cluster All Indicators On and Off with a scan tool. If the brake warning indicator does not turn ON and OFF Replace the P16 Instrument Cluster. If the brake warning indicator turns ON and OFF
6. All OK.

Note. Circuit/System Verification must be performed before Circuit/System Testing.

Brake Fluid Level Sensor Malfunction

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B20 Brake Fluid Level Switch. It may take up to 2 min for all vehicle systems to power down.
2. Test for less than 10 ohms between the ground circuit terminal 2 and ground. If 10 ohms or greater Ignition OFF. Test for less than 2 ohms in the ground circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, repair the open/high resistance in the ground connection. If less than 10 ohms
3. Ignition ON.
4. Verify the scan tool Brake Fluid Level Sensor parameter is Low. If the parameter is not Low Ignition OFF, disconnect the harness connector at the K9 Body Control Module. Test for infinite resistance between the signal circuit terminal 1 and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the K9 Body Control Module. If the parameter is Low
5. Install a 3 A fused jumper wire between the signal circuit terminal 1 and ground.
6. Verify the scan tool Brake Fluid Level Sensor parameter is OK. If the parameter is Low Ignition OFF, disconnect the harness connector at the K9 Body Control Module, ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V. Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K9 Body Control Module. If the parameter is OK
7. Test or replace the B20 Brake Fluid Level Switch.

Park Brake Switch Malfunction

1. Ignition OFF, disconnect the harness connector at the B80 Park Brake Switch.
2. Verify that the B80 Park Brake Switch has no physical damage or incorrect installation. If physical damage or incorrect installation is found Test or replace the B80 Park Brake Switch. If the inspection is OK
3. Ignition ON.
4. Verify the scan tool Park Brake Switch parameter is Released. If the parameter is Applied Ignition OFF, disconnect the harness connector at the K9 Body Control Module. Test for infinite resistance between the signal circuit terminal A and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the K9 Body Control Module. If the parameter is Released
5. Install a 3 A fused jumper wire between the signal circuit terminal A and ground.
6. Verify the scan tool Park Brake Switch parameter is Applied. If the parameter is Released Ignition OFF, disconnect the harness connector at the K9 Body Control Module, ignition ON. Test for less than 1 V between the signal circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V. Test for less than 2 ohms in the signal circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace theK9 Body Control Module. If the parameter is Applied
7. Test or replace the B80 Park Brake Switch.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Brake Fluid Level Indicator Switch Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system)
2. «Parking Brake Indicator Switch Replacement»(/buick/encore/i-2012-2016/remont/parking-brake-system/#parking-brake-system)
3. «Control Module References»(/buick/encore/i-2012-2016/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for body control module replacement, programming and setup.

Brake Pulsation

Brake Pulsation

Brake System Noise

Brake System Noise

Test Description

The number below refer to the step number on the diagnostic table

1. 5 Suspension components that are not operating properly may cause a disturbance to the vehicle during application of the brake system.
2. 6 Steering components that are not operating correctly may cause a disturbance to the vehicle during application of the brake system.

Braking Action Uneven - Pulls to One Side

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

1. 5 Suspension components that are not operating properly may cause a disturbance to the vehicle during application of the brake system.

Braking Action Uneven - Front to Rear

Brake Pedal Excessive Travel

Brake Pedal Excessive Travel

Brake Pedal Excessive Effort

Brake Pedal Excessive Effort

Brakes Drag

Brakes Drag

Brake System Slow Release

Brake System Slow Release

Brake Fluid Loss

Brake Fluid Loss

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.
3. 12 Disc brake rotor shields/backing plates that come in contact with disc brake rotors may cause brake system noise.

1. 15 Disc brake rotor thickness variation that exceeds the maximum acceptable level can cause brake pulsation.

1. 19 Disc brake rotor thickness variation that exceeds the maximum acceptable level can cause brake pulsation.

1. 22 Disc brake rotor assembled lateral runout (LRO) that exceeds the maximum acceptable level can lead to thickness variation.

Disc Brake System Diagnosis

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

1. 18 Drum brake backing plates that come in contact with brake drums may cause brake system noise.

Drum Brake System Diagnosis

Hydraulic Brake System Diagnosis

Brake Assist System Diagnosis

Brake Assist System Diagnosis

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»(/buick/encore/i-2012-2016/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

1. Start the engine and allow it to idle.
2. Visually inspect if the brake warning indicator 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»(/buick/encore/i-2012-2016/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 or Neutral, lightly apply the brake pedal. Observe both the pedal feel and the pedal travel. If the brake pedal apply felt spongy, or the pedal travel was excessive, DO NOT drive the vehicle until it is repaired. If the brake pedal apply did not feel spongy and the pedal travel was excessive, proceed to step 6.
6. Release and apply the brakes.
7. While continuing to apply the brakes, shift the transmission into DRIVE or 1st, 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.
8. 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. 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. If the brake pedal apply effort was not excessive and the pedal travel was not excessive, proceed to step 9.
9. 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 the assistant.
10. 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.
11. Select a smooth, dry, clean and level road that is as free of heavy traffic as possible for brake system moderate speed road testing.
12. Drive the vehicle at a moderate speed. Observe for a pull and/or incorrect tracking of the vehicle without the brakes applied.
13. 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. 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. If the brake pedal apply effort was not excessive and the pedal travel was not excessive, proceed to step 14.
14. 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.
15. 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.

Brake Pedal Travel Measurement and Inspection

Special Tools

CH-28662 Brake Pedal Effort Gauge

For equivalent regional tools, refer to Special Tools .

1. With the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal becomes firm, in order to deplete the brake booster power reserve.
2. Install the CH-28662 gauge (1), or equivalent, to the brake pedal (3).
3. Measure and record the distance (a) from the brake pedal (3) to the rim of the steering wheel (2). Note the points of measurement.
4. Apply and maintain a force of 445 N (100 lb) to the brake pedal, as indicated on the CH-28662 gauge (1), or equivalent.
5. While maintaining 445 N (100 lb) of force to the brake pedal (3), measure and record the distance (b) from the same point on the brake pedal (3) to the same point on the rim of the steering wheel (2).
6. Release the brake pedal (3) 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 for the 2 applies of the brakes.
8. Subtract the initial unapplied distance (a), from the average applied distance (b) to obtain the brake pedal travel measurement (c). Specification Maximum brake pedal travel - measured with the ignition OFF, brake booster power assist depleted, and the brakes cool.

Brake System Vacuum Source Test

Note. Engine temperature, accessory load, and elevation level will affect engine vacuum. Vacuum readings will decrease by approximately 2.7 kPa (0.8 in Hg) for every 305 m (1000 ft) of elevation above sea level.

1. Disconnect the engine vacuum hose from the vacuum brake booster check valve.
2. Install a vacuum gauge to the engine vacuum hose.
3. Install a scan tool to the vehicle.
4. Start the engine and allow the engine to idle until normal operating temperatures are reached.
5. With the vehicle in PARK or NEUTRAL with the park brake on, the engine idling, and the air conditioning (A/C) system OFF, check to see if the engine vacuum reading is the gauge pressure calculated from the pressure of the MAP sensor indicated on the scan tool.
6. Turn the ignition OFF.
7. If the engine vacuum reading is within the specified normal range, proceed to step 11.
8. 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, or brittleness
9. If any of these conditions were found with the engine vacuum hose, replace the hose, then repeat steps 2-5.
10. 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.
11. Remove the vacuum brake booster check valve from the booster.
12. Install the check valve to the engine vacuum hose.
13. Install the vacuum gauge to the check valve.
14. Start the engine and allow the engine to idle in park or neutral with the park brake on and with the A/C system OFF, until normal operating temperatures are reached.
15. Turn the ignition OFF.
16. Visually inspect the engine vacuum reading is maintained at the same gauge pressure as the pressure obtained form the MAP sensor as indicated on the scan tool.
17. If the engine vacuum reading is maintained within the specified normal range, proceed to step 19.
18. If the engine vacuum reading is NOT maintained within the specified normal range, replace the vacuum brake booster check valve, then repeat steps 12-16.
19. Inspect the vacuum brake booster check valve grommet for the following conditions: Loose connection to the vacuum brake booster Deformation or contamination Cracks, cuts or brittleness
20. If any of these conditions were found with the check valve grommet, replace the grommet.

Brake System External Leak Inspection

1. In order to inspect for external brake fluid leaks, first inspect 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»(/buick/encore/i-2012-2016/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 the ignition OFF.
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
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

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 the ignition OFF.
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»(/buick/encore/i-2012-2016/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 (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/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-vacuum brake booster retaining nuts. Carefully pull the master cylinder away from the vacuum brake 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 (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/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.

Disc Brake

1. With the tire and wheel assemblies removed and the brake rotors retained by wheel lug nuts, visually inspect the brake 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 brake caliper piston (1) in relation to the brake 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 brake caliper piston (1) for unrestricted and even movement during each apply of the brake system (5). Observe the brake caliper piston (1) for an unrestricted and even return motion during each release of the brake system (6).
5. If the brake 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 brake caliper may require overhaul or replacement.

Drum Brakes

1. With the rear tire and wheel assemblies and the brake drums removed, visually inspect the wheel cylinder pistons boot sealing areas to ensure that there are no brake fluid leaks.
2. If any evidence of a brake fluid leak is present, the brake wheel cylinder requires replacement.
3. Using firm hand pressure, simultaneously and evenly apply force on both brake shoes in order to compress the wheel cylinder pistons into their bore.
4. Evenly release the force from both brake shoes to allow the wheel cylinder pistons to return.
5. If one or both of the wheel cylinder pistons did not exhibit unrestricted and even movement during apply and/or release of force, the wheel cylinder may require replacement.

Brake Pipe and Hose Inspection

1. Visually inspect all of the brake pipes for the following conditions: Kinks, incorrect 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 correctly 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, perished, cracked, blistered, brittle or bulging hoses
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 inspect for soft spots (2), indicating an internal restriction. Inspect 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 (2) from the brake pedal.
2. Reposition the pedal pushrod boot (1) toward the front of the vehicle to expose as much of the pedal pushrod (2) as possible.
3. Inspect the brake pedal pushrod (2) for straightness.
4. If the brake pedal pushrod (2) is not straight, then the pushrod requires replacement.
5. Return the pedal pushrod boot (1) to its original position on the pedal pushrod (2).
6. Connect the brake pedal pushrod (2) to the brake pedal.

Master Cylinder Reservoir Filling

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

1. Remove and properly dispose of the brake fluid from the master cylinder reservoir.
2. Remove the brake master cylinder. Refer to «Master Cylinder Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
3. Remove and discard the brake master cylinder reservoir roll pin (1).
4. Remove the master cylinder reservoir (1) by carefully pulling straight upward.
5. Remove the brake fluid level indicator switch, if necessary. Refer to «Brake Fluid Level Indicator Switch Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
6. Remove the brake master cylinder reservoir seals (1).
7. If replacing the master cylinder reservoir, discard the reservoir seals.

Installation Procedure

1. Lightly lubricate the brake master cylinder reservoir seals (1) with GM approved brake fluid from a clean, sealed, brake fluid container.
2. Install the lubricated brake master cylinder reservoir seals to the brake master cylinder.
3. Install the master cylinder reservoir (1) by firmly pressing straight downward.
4. Install the brake fluid level indicator switch, if removed. Refer to «Brake Fluid Level Indicator Switch Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
5. Install a new brake master cylinder reservoir roll pin (1).
6. Install the brake master cylinder. Refer to «Master Cylinder Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

1. Place the ignition switch in the OFF position.
2. Remove the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
3. Disconnect the brake fluid level indicator switch electrical connector.
4. Using a suitable suction device, remove and properly discard the brake fluid from the brake master cylinder reservoir.
5. On manual transmission equipped vehicles, disconnect the clutch master cylinder reservoir hose (1).
6. Disconnect the master cylinder secondary brake pipe fitting (1).
7. Cap the brake pipe fitting and plug the master cylinder outlet port to prevent brake fluid loss and contamination.
8. Disconnect the master cylinder primary brake pipe fitting (1).
9. Cap the brake pipe fitting and plug the master cylinder outlet port to prevent brake fluid loss and contamination.
10. Remove the master cylinder nuts (1).
11. Remove the brake master cylinder.
12. Remove the master cylinder seal (1).
13. Inspect the master cylinder seal for damage or deterioration and replace, if necessary.
14. Remove the brake fluid level indicator switch, if necessary. Refer to «Brake Fluid Level Indicator Switch Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
15. Remove the master cylinder reservoir, if necessary. Refer to «Master Cylinder Reservoir Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

1. Install the master cylinder reservoir, if removed. Refer to «Master Cylinder Reservoir Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
2. Bench bleed the master cylinder. Refer to «Master Cylinder Bench Bleeding»(/buick/encore/i-2012-2016/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»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
4. Install the master cylinder seal (1).
5. Install the master cylinder to the power vacuum brake booster.
6. Install the master cylinder nuts (1) and tighten to 19 (14 lb ft).
7. Connect the master cylinder primary brake pipe fitting (1) and tighten to 18 N.m (13 lb ft).
8. Connect the master cylinder secondary brake pipe fitting (1) and tighten to 18 N.m (13 lb ft).
9. On manual transmission equipped vehicles, connect the clutch master cylinder reservoir hose (1).
10. Connect the brake fluid level indicator switch electrical connector.
11. Install the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
12. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

Master Cylinder Bench Bleeding

1. Secure the mounting flange of the brake master cylinder in a bench vice 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 the maximum fill level with brake fluid from a clean, sealed brake fluid container. Refer to «Master Cylinder Reservoir Filling»(/buick/encore/i-2012-2016/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 vice.

1. Disconnect the brake fluid level indicator switch electrical connector.
2. Using a small, flat-bladed tool, lift the locking tab on the underside of the brake fluid level indicator switch (1) and remove the switch.
3. Inspect the master cylinder reservoir for damage and replace, if necessary. Refer to «Master Cylinder Reservoir Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

1. Install the master cylinder reservoir, if removed. Refer to «Master Cylinder Reservoir Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
2. Install the brake fluid level indicator switch (1) by pressing the switch firmly into the brake master cylinder reservoir.
3. Connect the brake fluid level indicator switch electrical connector.

1. Remove the battery tray. Refer to «Battery Tray Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
2. Remove the power vacuum brake booster bolts (1).
3. Remove the brake pedal assembly upper nuts (1)
4. Remove the brake pedal assembly lower nuts (1)
5. Remove the steering column. Refer to «Steering Column Replacement (Mexico, N40)»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#steering-wheel-and-steering-column) , «Steering Column Replacement (Canada, NJ1)»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#steering-wheel-and-steering-column) , «Steering Column Replacement (United States, NJ1)»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#steering-wheel-and-steering-column) .
6. Remove the brake pedal release bracket bolt (1).
7. Remove the brake pedal release bracket bolts (1).
8. Remove the brake pedal release bracket (1).
9. Remove the brake pedal position sensor. Refer to «Brake Pedal Position Sensor Replacement»(/buick/encore/i-2012-2016/remont/exterior-lights/#lighting-system-repair-instructions__brake-pedal-position-sensor-replacement) .
10. On manual transmission equipped vehicles, remove the clutch pedal position sensor. Refer to «Clutch Pedal Position Sensor Replacement»(/buick/encore/i-2012-2016/remont/clutches-manual-hydraulic/#manual-transmission-clutch) .
11. Remove the accelerator pedal position sensor. Refer to «Accelerator Pedal Position Sensor Replacement»(/buick/encore/i-2012-2016/remont/testing-diagnostics/#engine-controls-and-fuel-14l-luj-luv-repair-instructions) .
12. On manual transmission equipped vehicles, compress the clutch master cylinder pushrod locking tabs (1) and release the clutch pedal by lifting the pedal upward.
13. On manual transmission equipped vehicles, remove the clutch master cylinder bolts (1) and position the clutch master cylinder aside. Refer to «Clutch Master Cylinder Replacement»(/buick/encore/i-2012-2016/remont/clutches-manual-hydraulic/#manual-transmission-clutch) .
14. Position aside any wiring harnesses attached to the brake pedal assembly bracket, as necessary.
15. Remove the 2 upper brake pedal assembly bolts (1).
16. Pull the brake pedal assembly away from the dash panel.
17. From behind the brake pedal assembly, remove the brake pedal assembly bracket nut (1).
18. Remove the brake pedal assembly bracket (1).
19. Remove the brake pedal assembly from the vehicle.
20. Remove any necessary components from the brake pedal assembly.

1. Install any removed components from the brake pedal assembly.
2. Install the brake pedal assembly to the vehicle.
3. Install the brake pedal assembly bracket (1).
4. Pull the brake pedal assembly away from the dash panel.
5. From behind the brake pedal assembly, install the brake pedal assembly bracket nut (1) and tighten to 9 (80 lb in).
6. Install the brake pedal assembly lower nuts (1) and tighten to 19 N.m (14 lb ft).
7. Install the brake pedal assembly upper nuts (1) and tighten to 19 N.m (14 lb ft).
8. Install the 2 upper brake pedal assembly bolts (1) and tighten to 9 N.m (80 lb in).
9. Reposition any wiring harnesses attached to the brake pedal assembly bracket, as necessary.
10. On manual transmission equipped vehicles, install the clutch master cylinder and bolts (1). Refer to «Clutch Master Cylinder Replacement»(/buick/encore/i-2012-2016/remont/clutches-manual-hydraulic/#manual-transmission-clutch) .
11. On manual transmission equipped vehicles, compress the clutch master cylinder pushrod locking tabs (1) and install the clutch pedal to the clutch master cylinder pushrod.
12. Install the brake pedal position sensor. Refer to «Brake Pedal Position Sensor Replacement»(/buick/encore/i-2012-2016/remont/exterior-lights/#lighting-system-repair-instructions__brake-pedal-position-sensor-replacement) .
13. On manual transmission equipped vehicles, install the clutch pedal position sensor. Refer to «Clutch Pedal Position Sensor Replacement»(/buick/encore/i-2012-2016/remont/clutches-manual-hydraulic/#manual-transmission-clutch) .
14. Install the accelerator pedal position sensor. Refer to «Accelerator Pedal Position Sensor Replacement»(/buick/encore/i-2012-2016/remont/testing-diagnostics/#engine-controls-and-fuel-14l-luj-luv-repair-instructions) .
15. Install the brake pedal release bracket (1).
16. Install the brake pedal release bracket bolts (1) and tighten to 22 N.m (16 lb ft).
17. Install the brake pedal release bracket bolt (1) and tighten to 22 N.m (16 lb ft).
18. Connect the brake pedal position sensor electrical connector.
19. Install the steering column. Refer to «Steering Column Replacement (Mexico, N40)»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#steering-wheel-and-steering-column) , «Steering Column Replacement (Canada, NJ1)»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#steering-wheel-and-steering-column) , «Steering Column Replacement (United States, NJ1)»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#steering-wheel-and-steering-column) .
20. Install the power vacuum brake booster bolts (1) and tighten to 19 N.m (14 lb ft).
21. Install the battery tray. Refer to «Battery Tray Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .

1. Remove the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
2. Clean the area surrounding the proportion valve of any accumulated dirt and debris.
3. Disconnect the master cylinder secondary brake pipe fitting (1) from the brake proportion valve.
4. Cap the brake pipe fitting and plug the proportion valve inlet port to prevent brake fluid loss and contamination.
5. Disconnect the master cylinder primary brake pipe fitting (1) from the brake proportion valve.
6. Cap the brake pipe fitting and plug the proportion valve inlet port to prevent brake fluid loss and contamination.
7. Disconnect the right rear brake pipe fitting (1).
8. Cap the brake pipe fitting and plug the proportion valve outlet port to prevent brake fluid loss and contamination.
9. Disconnect the left front brake pipe fitting (1).
10. Cap the brake pipe fitting and plug the proportion valve outlet port to prevent brake fluid loss and contamination.
11. Disconnect the right front brake pipe fitting (1).
12. Cap the brake pipe fitting and plug the proportion valve outlet port to prevent brake fluid loss and contamination.
13. Disconnect the left rear brake pipe fitting (1).
14. Cap the brake pipe fitting and plug the proportion valve outlet port to prevent brake fluid loss and contamination.
15. Remove the proportion valve nut (1).
16. Remove the proportion valve (1).

1. Install the proportion valve (1).
2. Install the proportion valve nut (1) and tighten to 15 (11 lb ft).
3. Connect the left rear brake pipe fitting (1) and tighten to 18 (13 lb ft).
4. Connect the right front brake pipe fitting (1) and tighten to 18 (13 lb ft).
5. Connect the left front brake pipe fitting (1) and tighten to 18 (13 lb ft).
6. Connect the right rear brake pipe fitting (1) and tighten to 18 (13 lb ft).
7. Connect the master cylinder primary brake pipe fitting (1) to the brake proportion valve and tighten to 18 (13 lb ft).
8. Connect the master cylinder secondary brake pipe fitting (1) to the brake proportion valve and tighten to 18 (13 lb ft).
9. Install the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
10. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

1. Remove the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
2. Disconnect the brake pressure modulator valve (BPMV) front pipe fitting (1) from the master cylinder.
3. Plug the master cylinder outlet port to prevent brake fluid loss and contamination.
4. Disconnect the BPMV front pipe fitting (1) from the BPMV.
5. Plug the BPMV inlet port to prevent brake fluid loss and contamination.
6. Remove the brake pipe from the vehicle.

1. Install the brake pipe to the vehicle.
2. Install the BPMV front pipe fitting (1) to the BPMV and tighten the fitting to 18 N.m (13 lb ft).
3. Install the BPMV front pipe fitting (1) to the master cylinder and tighten the fitting to 18 N.m (13 lb ft).
4. Install the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
5. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

1. Remove the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
2. Disconnect the brake pressure modulator valve (BPMV) rear pipe fitting (1) from the master cylinder.
3. Plug the master cylinder outlet port to prevent brake fluid loss and contamination.
4. Disconnect the BPMV rear pipe fitting (1) from the BPMV.
5. Plug the BPMV inlet port to prevent brake fluid loss and contamination.
6. Remove the brake pipe from the vehicle.

1. Install the brake pipe to the vehicle.
2. Install the BPMV pipe fitting (1) to the BPMV and tighten the fitting to 18 N.m (13 lb ft).
3. Install the BPMV front pipe fitting (1) to the master cylinder and tighten the fitting to 18 N.m (13 lb ft).
4. Install the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
5. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

1. Remove the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
2. Disconnect the brake pressure modulator valve (BPMV) front brake pipe fitting (1) from the BPMV.
3. Plug the BPMV outlet port to prevent brake fluid loss and contamination.
4. Release the BPMV front brake pipe from the retaining clip (1).
5. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
6. Remove the left front tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .
7. Disconnect the BPMV front brake pipe fitting (1) from the left front brake hose.
8. Remove the BPMV front brake pipe from the vehicle.

1. Install the BPMV front brake pipe to the vehicle.
2. Position, but do not secure, the BPMV front brake pipe to the retaining clip.
3. Install the BPMV front brake pipe fitting (1) to the left front brake hose and tighten the fitting to 18 N.m (13 lb ft).
4. Lower the vehicle to access the brake pipe retaining clip.
5. Secure the BPMV front brake pipe to the retaining clip (1).
6. Install the BPMV front brake pipe fitting (1) to the BPMV and tighten the fitting to 18 N.m (13 lb ft).
7. Install the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
8. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
9. Install the left front tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .

1. Remove the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
2. Disconnect the brake pressure modulator valve (BPMV) front brake pipe fitting (1) from the BPMV.
3. Plug the BPMV outlet port to prevent brake fluid loss and contamination.
4. Release the BPMV front brake pipe from the retaining clips (1).
5. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
6. Release the BPMV front brake pipe from the retaining clip (1).
7. Remove the right front tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .
8. Disconnect the BPMV front brake pipe fitting (1) from the right front brake hose.
9. Remove the BPMV front brake pipe from the vehicle.

1. Install the BPMV front brake pipe to the vehicle.
2. Position, but do not secure, the BPMV front brake pipe to the retaining clips.
3. Install the BPMV front brake pipe fitting (1) to the right front brake hose and tighten the fitting to 18 N.m (13 lb ft).
4. Secure the BPMV front brake pipe to the retaining clip (1).
5. Lower the vehicle to access the upper brake pipe retaining clips.
6. Secure the BPMV front brake pipe to the retaining clips (1).
7. Install the BPMV front brake pipe fitting (1) to the BPMV and tighten the fitting to 18 N.m (13 lb ft).
8. Install the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
9. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
10. Install the right front tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .

Brake Pipe Replacement

Special Tools

CH-45405 Brake Pipe Flaring Tool Kit

For equivalent regional tools, refer to Special Tools .

1. Inspect the area of brake pipe to be repaired or 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 CH-45405 Brake Pipe Flaring Tool Kit. 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 9.50 mm (0.374 in) for 6.35 mm (1/4 in) diameter pipe 12.67 mm (0.499 in) for 7.94 mm (5/16 in) diameter pipe
6. Using the pipe cutter included in the CH-45405 Brake Pipe Flaring Tool Kit , carefully cut the brake pipe squarely to the measured length.
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 end to be flared, if necessary. Select the appropriate blade on the coating stripping tool included in the CH-45405 Brake Pipe Flaring Tool Kit , by unthreading the blade block from the stripping tool and installing the block with the desired blade facing the tool rollers. Specification 6.35 mm (0.250 in) blade for 4.76 mm (3/16 in) diameter pipe 9.50 mm (0.374 in) blade for 6.35 mm (1/4 in) and 7.94 mm (5/16 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 9.50 mm (0.374 in) for 6.35 mm (1/4 in) and 7.94 mm (5/16 in) diameter pipe
10. Chamfer the inside and outside diameter of the pipe with the de-burring tool included in the CH-45405 Brake Pipe Flaring Tool Kit.
11. Install the tube nuts on the brake pipe, noting their orientation.
12. Clean the brake pipe and the CH-45405 Brake Pipe Flaring Tool Kit of lubricant, contaminants, and debris.
13. Loosen the die clamping screw of the CH-45405 Brake Pipe Flaring Tool Kit.
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 CH-45405 Brake Pipe Flaring Tool Kit until it bottoms against the die cage.
23. While guiding the forming mandrel into the exposed end of pipe to be flared, operate the lever of the CH-45405 Pipe Flaring Tool Kit until the forming mandrel bottoms against the clamping dies.
24. Rotate the hydraulic fluid control valve counterclockwise to the open position to allow the hydraulic forming ram to retract.
25. Insert the finishing cone into the forming ram.
26. Rotate the hydraulic fluid control valve clockwise to the closed position.
27. Rotate the body of the CH-45405 Brake Pipe Flaring Tool Kit until it bottoms against the die cage.
28. While guiding the finishing cone into the exposed end of pipe to be flared, operate the lever of the CH-45405 Brake Pipe Flaring Tool Kit until the finishing cone bottoms against the dies.
29. Rotate the hydraulic fluid control valve counterclockwise to the open position to allow the hydraulic forming ram to retract.
30. Loosen the die clamping screw and remove the dies and pipe.
31. If necessary, lightly tap the dies until the die halves separate.
32. Inspect the brake pipe flare for correct shape and diameter (a). Specification 6.74-7.10 mm (0.265-0.279 in) flare diameter for 4.76 mm (3/16 in) diameter pipe 8.57-9.27 mm (0.344-0.358 in) flare diameter for 6.35 mm (1/4 in) diameter pipe 10.42-10.79 mm (0.410-0.425 in) flare diameter for 7.94 mm (5/16 in) diameter pipe
33. If necessary, using the removed section of brake 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.
34. Install the pipe to the vehicle with the appropriate brake pipe unions, as required.
35. If previously released, secure the brake pipe to the retainers.
36. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
37. With the aid of an assistant, inspect the brake pipe flares for leaks by starting the engine and applying the brakes.

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
2. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .
3. Remove the brake pipe fitting (1) from the front brake hose.
4. Cap the brake pipe fitting to prevent brake fluid loss and contamination.
5. Remove the brake hose retainer (1).
6. Release the brake hose grommet (1) from the strut bracket.
7. Remove the brake hose fitting bolt (1).
8. Remove and discard the brake hose fitting gaskets (2) from the brake hose fitting (3).
9. Remove the brake hose.

1. Assemble the brake hose fitting bolt (1) and the new brake hose fitting gaskets (2) to the brake hose fitting (3).
2. Install the brake hose assembly to the brake caliper and tighten the fitting bolt to 40 (30 lb ft).
3. Install the brake hose grommet (1) to the strut bracket.
4. Install the brake hose to the wheelhouse bracket and install the retainer (1).
5. Install the brake pipe fitting (1) to the front brake hose and tighten the fitting to 18 (13 lb ft).
6. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
7. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .

1. Remove the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
2. Disconnect the left rear intermediate pipe fitting (1) from the brake pressure modulator valve (BPMV).
3. Plug the BPMV outlet port to prevent brake fluid loss and contamination.
4. Release the left rear intermediate pipe from the retaining clips (1).
5. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
6. Release the left rear intermediate pipe from the retaining clip (1).
7. Release the left rear intermediate pipe from the front floor retaining clips (1).
8. Remove the 2 nuts and the underbody cross sill shield (1).
9. Remove the fuel tank. Refer to «Fuel Tank Replacement (AWD)»(/buick/encore/i-2012-2016/remont/testing-diagnostics/#engine-controls-and-fuel-14l-luj-luv-repair-instructions) .
10. Release the left rear intermediate pipe from the rear floor retaining clips (1).
11. Release the left rear intermediate pipe from the retaining clips (1).
12. Release the left rear intermediate pipe from the cross vehicle retaining clips (1).
13. Release the left rear intermediate pipe from the left rail retaining clips (1).
14. Release the left rear intermediate pipe from the left rear rail retaining clips (1).
15. Disconnect the left rear intermediate pipe fitting (1) from the rear brake hose fitting.
16. Cap the brake hose fitting to prevent brake fluid loss and contamination.
17. Remove the left rear intermediate pipe from the vehicle.

1. Install the left rear intermediate pipe from the vehicle.
2. Position, but do not secure, the left rear intermediate pipe to the retaining clips.
3. Install the left rear intermediate pipe fitting (1) to the rear brake hose fitting and tighten the fitting to 18 (13 lb ft).
4. Secure the left rear intermediate pipe to the left rear rail retaining clips (1).
5. Secure the left rear intermediate pipe to the left rail retaining clips (1).
6. Secure the left rear intermediate pipe to the cross vehicle retaining clips (1).
7. Secure the left rear intermediate pipe to the retaining clips (1).
8. Secure the left rear intermediate pipe to the rear floor retaining clips (1).
9. Install the fuel tank. Refer to «Fuel Tank Replacement (AWD)»(/buick/encore/i-2012-2016/remont/testing-diagnostics/#engine-controls-and-fuel-14l-luj-luv-repair-instructions) .
10. Install the underbody cross sill shield (1) and the 2 nuts.
11. Secure the left rear intermediate pipe to the front floor retaining clips (1).
12. Secure the left rear intermediate pipe to the retaining clip (1).
13. Secure the left rear intermediate pipe to the retaining clips (1).
14. Connect the left rear intermediate pipe fitting (1) to the BPMV and tighten the fitting to 18 (13 lb ft).
15. Install the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
16. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

1. Remove the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
2. Disconnect the right rear intermediate pipe fitting (1) from the brake pressure modulator valve (BPMV).
3. Plug the BPMV outlet port to prevent brake fluid loss and contamination.
4. Release the right rear intermediate pipe from the retaining clips (1).
5. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
6. Release the right rear intermediate pipe from the retaining clip (1).
7. Release the right rear intermediate pipe from the front floor retaining clips (1).
8. Remove the 2 nuts and the underbody cross sill shield (1).
9. Remove the fuel tank. Refer to «Fuel Tank Replacement (AWD)»(/buick/encore/i-2012-2016/remont/testing-diagnostics/#engine-controls-and-fuel-14l-luj-luv-repair-instructions) .
10. Release the right rear intermediate pipe from the rear floor retaining clips (1).
11. Release the right rear intermediate pipe from the retaining clips (1).
12. Release the right rear intermediate pipe from the right rail retaining clips (1).
13. Release the right rear intermediate pipe from the right rear rail retaining clips (1).
14. Disconnect the right rear intermediate pipe fitting (1) from the rear brake hose fitting.
15. Cap the brake hose fitting to prevent brake fluid loss and contamination.
16. Remove the right rear intermediate pipe from the vehicle.

1. Install the right rear intermediate pipe to the vehicle.
2. Position, but do not secure, the right rear intermediate pipe to the retaining clips.
3. Install the right rear intermediate pipe fitting (1) to the rear brake hose fitting and tighten the fitting to 18 (13 lb ft).
4. Secure the right rear intermediate pipe to the right rear rail retaining clips (1).
5. Secure the right rear intermediate pipe to the right rail retaining clips (1).
6. Secure the right rear intermediate pipe to the retaining clips (1).
7. Secure the right rear intermediate pipe to the rear floor retaining clips (1).
8. Install the fuel tank. Refer to «Fuel Tank Replacement (AWD)»(/buick/encore/i-2012-2016/remont/testing-diagnostics/#engine-controls-and-fuel-14l-luj-luv-repair-instructions) .
9. Install the underbody cross sill shield (1) and the 2 nuts.
10. Secure the right rear intermediate pipe to the front floor retaining clips (1).
11. Secure the right rear intermediate pipe to the retaining clip (1).
12. Secure the right rear intermediate pipe to the retaining clips (1).
13. Connect the right rear intermediate pipe fitting (1) to the BPMV and tighten the fitting to 18 (13 lb ft).
14. Install the battery. Refer to «Battery Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
15. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
2. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .
3. Disconnect the rear brake rear pipe fitting (1) from the rear brake hose.
4. Cap the brake hose fitting to prevent brake fluid loss and contamination.
5. Disconnect the rear brake rear pipe fitting (1) from the rear brake cylinder.
6. Remove the rear brake rear pipe from the vehicle.

1. Install the rear brake rear pipe to the vehicle.
2. Install the rear brake rear pipe fitting (1) to the rear brake cylinder and tighten the fitting to 18 (13 lb ft).
3. Install the rear brake rear pipe fitting (1) to the rear brake hose and tighten the fitting to 18 (13 lb ft).
4. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
5. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
2. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .
3. Remove the brake pipe fitting (1) from the rear brake hose.
4. Cap the brake pipe fitting to prevent brake fluid loss and contamination.
5. Remove the brake hose retainer (1).
6. Remove the brake pipe fitting (1) from the rear brake hose.
7. Cap the brake pipe fitting to prevent brake fluid loss and contamination.
8. Remove the brake hose retainer (1).
9. Remove the brake hose.

1. Install the brake hose.
2. Install the brake hose retainer (1).
3. Install the brake pipe fitting (1) to the rear brake hose and tighten the fitting to 18 (13 lb ft).
4. Install the brake hose to the wheelhouse bracket and install the retainer (1).
5. Install the brake pipe fitting (1) to the rear brake hose and tighten the fitting to 18 (13 lb ft).
6. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
7. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
2. Remove the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .
3. Remove the brake pipe fitting (1) from the rear brake hose.
4. Cap the brake pipe fitting to prevent brake fluid loss and contamination.
5. Remove the brake hose retainer (1).
6. Remove the brake hose fitting bolt (1).
7. Remove and discard the brake hose fitting gaskets (2) from the brake hose fitting (3).
8. Remove the brake hose.

1. Assemble the brake hose fitting bolt (1) and the new brake hose fitting gaskets (2) to the brake hose fitting (3).
2. Install the brake hose assembly to the brake caliper and tighten the fitting bolt to 40 (30 lb ft).
3. Install the brake hose to the wheelhouse bracket and install the retainer (1).
4. Install the brake pipe fitting (1) to the rear brake hose and tighten the fitting to 18 (13 lb ft).
5. Bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
6. Install the tire and wheel assembly. Refer to «Tire and Wheel Removal and Installation»(/buick/encore/i-2012-2016/remont/wheel-tire-system/#tires-and-wheels__tire-and-wheel-removal-and-installation) .

If hydraulic components were serviced on only one wheel hydraulic circuit, perform the following procedure.

Bleeding a Single Hydraulic Brake Circuit

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. Place a clean shop cloth beneath the brake master cylinder to catch brake fluid spills.
3. Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and diaphragm.
4. Fill the brake master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Add brake fluid as needed to ensure that the brake master cylinder reservoir remains at least half-full throughout the bleed procedure. The reservoir cap must be installed at all times except when filling the reservoir. Refer to «Fluid and Lubricant Recommendations»(/buick/encore/i-2012-2016/remont/lubrication-system/#maintenance-and-lubrication__fluid-and-lubricant-recommendations) .
5. Install a proper box-end wrench onto the wheel hydraulic circuit bleeder valve which has been serviced.
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 brake fluid from a clean, sealed brake fluid container.
8. Have an assistant slowly press 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 wheel hydraulic circuit.
12. After all air has been purged from the hydraulic circuit, tighten the bleeder valve and install the dust cap.
13. Fill the brake master cylinder reservoir to the maximum-fill level with GM approved brake fluid from a clean, sealed brake fluid container.
14. Slowly press and release the brake pedal. Observe the brake pedal feel.
15. If the brake pedal feels spongy, perform the Bleeding the Complete Brake Hydraulic System procedure
16. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp remains illuminated.
17. If the brake system warning lamp remains illuminated, refer to «Diagnostic Starting Point - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-starting-point-vehicle) .

Bleeding the Complete Brake Hydraulic System

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. Place a clean shop cloth beneath the brake master cylinder to catch brake fluid spills.
3. Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and diaphragm.
4. Fill the brake master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Add brake fluid as needed to ensure that the brake master cylinder reservoir remains at least half-full throughout the bleed procedure. The reservoir cap must be installed at all times except when filling the reservoir. Refer to «Fluid and Lubricant Recommendations»(/buick/encore/i-2012-2016/remont/lubrication-system/#maintenance-and-lubrication__fluid-and-lubricant-recommendations) .
5. If the master cylinder was replaced, the master cylinder must be bench bled. Refer to «Master Cylinder Bench Bleeding»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-bench-bleeding) .
6. If the brake pipes have been removed from the master cylinder, the following steps must be performed. With the rear brake pipe installed securely to the master cylinder, loosen and separate the front brake pipe fitting 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. Capture and properly dispose of the brake fluid in an approved container. Install the front brake pipe fitting to the front port of the brake master cylinder and tighten the fitting. Refer to «Fastener Tightening Specifications»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__fastener-tightening-specifications) . Have an assistant slowly press the brake pedal fully and maintain steady pressure on the pedal. Loosen the front brake pipe fitting from the front port of the brake master cylinder to purge air from the master cylinder port. Tighten the front brake pipe fitting, then have the assistant slowly release the brake pedal. Wait 15 seconds, then repeat steps 6.4-6.6 until all air is purged from the front brake pipe fitting of the front port of the master cylinder. After all air is purged from the front port of the brake master cylinder, tighten the front master cylinder brake pipe fitting. Refer to «Fastener Tightening Specifications»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__fastener-tightening-specifications) . With the front brake pipe fitting installed securely to the front port of the brake master cylinder, loosen and separate the rear brake pipe fitting from the rear port of the brake master cylinder. Repeat steps 6.2-6.7 for the rear port of the brake master cylinder. After all air is purged from the rear port of the brake master cylinder, tighten the rear master cylinder brake pipe fitting. Refer to «Fastener Tightening Specifications»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__fastener-tightening-specifications) . Slowly press and release the brake pedal. Observe the brake pedal feel. If the brake pedal feels spongy, proceed to step 7. If the brake pedal feels firm, proceed to step 24.
7. If the brake pipes have been removed from the brake pressure modulator valve (BPMV) assembly, if equipped, or the brake proportion valve assembly, if equipped, air must be purged from each port of the respective assembly beginning with the feed pipes from the master cylinder. Loosen and separate one of the master cylinder brake pipe fittings from the inlet port of the assembly to be bled. Allow a small amount of brake fluid to gravity bleed from the open port of the assembly. Capture and properly dispose of the brake fluid in an approved container. Install the brake pipe fitting and to the inlet port of the assembly and tighten securely. Have an assistant slowly press the brake pedal fully and maintain steady pressure on the pedal. Loosen the same brake pipe fitting to purge air from the open port of the assembly. Tighten the brake pipe fitting, then have the assistant slowly release the brake pedal. Wait 15 seconds, then repeat steps 7.4-7.6 until all air is purged from the brake pipe fitting of the assembly. Repeat steps 7.1-7.7 for all of the remaining ports of the assembly. After bleeding each port of the assembly, tighten all of the brake pipe fittings on the assembly. Refer to «Fastener Tightening Specifications»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__fastener-tightening-specifications) . Fill the master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Slowly press and release the brake pedal. Observe the brake pedal feel. If the brake pedal feels spongy, proceed to step 8. If the brake pedal feels firm, proceed to step 24.
8. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
9. Install a transparent hose over the end of the bleeder valve.
10. 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.
11. Have an assistant slowly press the brake pedal fully and maintain steady pressure on the brake pedal.
12. Loosen the bleeder valve to purge air from the wheel hydraulic circuit.
13. Tighten the bleeder valve, then have the assistant slowly release the brake pedal.
14. Wait 15 seconds, then repeat steps 11-13 until all air is purged from the wheel hydraulic circuit.
15. Tighten the RIGHT REAR hydraulic wheel circuit bleeder valve securely.
16. Install a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve, then repeat steps 9-14..
17. Install a proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve, then repeat steps 9-14..
18. Install a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve, then repeat steps 9-14..
19. After completing the final wheel hydraulic circuit bleeding procedure, tighten all of the wheel hydraulic circuit bleeder valves and install the bleeder valve dust caps.
20. Fill the master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container.
21. Slowly press and release the brake pedal. Observe the brake pedal feel.
22. If the brake pedal feels spongy, perform the following procedure. If equipped with antilock brakes, install a scan tool and perform the «Antilock Brake System Automated Bleed»(/buick/encore/i-2012-2016/remont/anti-locktraction-control/#antilock-brake-system) to remove air which may be trapped in the BPMV. Inspect the hydraulic brake system for external leaks. Refer to «Brake System External Leak Inspection»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-system-external-leak-inspection) . Repeat the Bleeding the Complete Brake Hydraulic System procedure.
23. If the brake pedal still feels spongy, pressure bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system)
24. Turn the ignition switch ON with the engine OFF. Check to see if the brake system warning lamp remains illuminated.
25. If the brake system warning lamp remains illuminated, refer to «Diagnostic Starting Point - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-starting-point-vehicle) .

If hydraulic components were serviced on only one wheel hydraulic circuit, perform the following procedure.

Bleeding a Single Hydraulic Brake Circuit

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. Place a clean shop cloth beneath the brake master cylinder to catch brake fluid spills.
3. Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and diaphragm.
4. Fill the brake master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Refer to «Fluid and Lubricant Recommendations»(/buick/encore/i-2012-2016/remont/lubrication-system/#maintenance-and-lubrication__fluid-and-lubricant-recommendations) .
5. Following the brake pressure bleeder manufacturer's instructions, fill the brake pressure bleeder with GM approved brake fluid from a clean, sealed brake fluid container.
6. Install the appropriate master cylinder reservoir adapter and connect the brake pressure bleeder.
7. Charge the brake pressure bleeder air tank to 170-200 kPa/1.7-2.0 bar (25-30 psi), or as recommended by the brake pressure bleeder manufacturer's instructions.
8. Open the brake pressure bleeder fluid tank valve to allow pressurized brake fluid to enter the brake hydraulic system.
9. Wait approximately 30 seconds, then inspect the entire hydraulic brake system for external brake fluid leaks.
10. Install a proper box-end wrench onto the wheel hydraulic circuit bleeder valve which has been serviced.
11. Install a transparent hose over the end of the bleeder valve.
12. Submerge the open end of the transparent hose into a transparent container partially filled with brake fluid from a clean, sealed brake fluid container.
13. Loosen the bleeder valve to purge air from the wheel hydraulic circuit.
14. Allow fluid to flow until air bubbles stop flowing from the bleeder.
15. After all air has been purged from the hydraulic circuit, tighten the bleeder valve and install the dust cap.
16. Close the brake pressure bleeder fluid tank valve then disconnect the brake pressure bleeder from the master cylinder reservoir bleeder adapter.
17. Remove the master cylinder reservoir bleeder adapter from the master cylinder reservoir.
18. Fill the brake master cylinder reservoir to the maximum-fill level with GM approved brake fluid from a clean, sealed brake fluid container.
19. Slowly press and release the brake pedal. Observe the brake pedal feel.
20. If the brake pedal feels spongy, perform the Bleeding the Complete Brake Hydraulic System procedure
21. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp remains illuminated.
22. If the brake system warning lamp remains illuminated, refer to «Diagnostic Starting Point - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-starting-point-vehicle) .

Bleeding the Complete Brake Hydraulic System

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. Place a clean shop cloth beneath the brake master cylinder to catch brake fluid spills.
3. Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and diaphragm.
4. Fill the brake master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Refer to «Fluid and Lubricant Recommendations»(/buick/encore/i-2012-2016/remont/lubrication-system/#maintenance-and-lubrication__fluid-and-lubricant-recommendations) .
5. If the master cylinder was replaced, the master cylinder must be bench bled. Refer to «Master Cylinder Bench Bleeding»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__master-cylinder-bench-bleeding) .
6. If the brake pipes have been removed from the master cylinder, the following steps must be performed. With the rear brake pipe installed securely to the master cylinder, loosen and separate the front brake pipe fitting 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. Capture and properly dispose of the brake fluid in an approved container. Install the front brake pipe fitting to the front port of the brake master cylinder and tighten the fitting. Have an assistant slowly press the brake pedal fully and maintain steady pressure on the pedal. Loosen the front brake pipe fitting from the front port of the brake master cylinder to purge air from the master cylinder port. Tighten the front brake pipe fitting, then have the assistant slowly release the brake pedal. Wait 15 seconds, then repeat steps 6.4-6.6 until all air is purged from the front brake pipe fitting of the front port of the master cylinder. After all air is purged from the front port of the brake master cylinder, tighten the front master cylinder brake pipe fitting. Refer to «Fastener Tightening Specifications»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__fastener-tightening-specifications) . With the front brake pipe fitting installed securely to the front port of the brake master cylinder, loosen and separate the rear brake pipe fitting from the rear port of the brake master cylinder. Repeat steps 6.2-6.7 for the rear port of the brake master cylinder. After all air is purged from the rear port of the brake master cylinder, tighten the rear master cylinder brake pipe fitting. Refer to «Fastener Tightening Specifications»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__fastener-tightening-specifications) . Slowly press and release the brake pedal. Observe the brake pedal feel. If the brake pedal feels spongy, proceed to step 7. If the brake pedal feels firm, proceed to step 24.
7. If the brake pipes have been removed from the brake pressure modulator valve (BPMV) assembly, if equipped, or the brake proportion valve assembly, if equipped, air must be purged from each port of the respective assembly beginning with the feed pipes from the master cylinder. Loosen and separate one of the master cylinder brake pipe fittings from the inlet port of the assembly to be bled. Allow a small amount of brake fluid to gravity bleed from the open port of the assembly. Capture and properly dispose of the brake fluid in an approved container. Install the brake pipe fitting and to the inlet port of the assembly and tighten securely. Have an assistant slowly press the brake pedal fully and maintain steady pressure on the pedal. Loosen the same brake pipe fitting to purge air from the open port of the assembly. Tighten the brake pipe fitting, then have the assistant slowly release the brake pedal. Wait 15 seconds, then repeat steps 7.4-7.6 until all air is purged from the brake pipe fitting of the assembly. Repeat steps 7.1-7.7 for all of the remaining ports of the assembly. After bleeding each port of the assembly, tighten all of the brake pipe fittings on the assembly. Refer to «Fastener Tightening Specifications»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__fastener-tightening-specifications) . Fill the master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Slowly press and release the brake pedal. Observe the brake pedal feel. If the brake pedal feels spongy, proceed to step 8. If the brake pedal feels firm, proceed to step 24.
8. Following the brake pressure bleeder manufacturer's instructions, fill the brake pressure bleeder with GM approved brake fluid from a clean, sealed brake fluid container.
9. Install the appropriate master cylinder reservoir adapter and connect the brake pressure bleeder.
10. Charge the brake pressure bleeder air tank to 170-200 kPa/1.7-2.0 bar (25-30 psi), or as recommended by the brake pressure bleeder manufacturer's instructions.
11. Open the brake pressure bleeder fluid tank valve to allow pressurized brake fluid to enter the brake hydraulic system.
12. Wait approximately 30 seconds, then inspect the entire hydraulic brake system for external brake fluid leaks.
13. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
14. Install a transparent hose over the end of the bleeder valve.
15. 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.
16. Have an assistant slowly press the brake pedal fully and maintain steady pressure on the brake pedal.
17. Loosen the bleeder valve to purge air from the wheel hydraulic circuit.
18. Tighten the bleeder valve, then have the assistant slowly release the brake pedal.
19. Wait 15 seconds, then repeat steps 11-13 until all air is purged from the wheel hydraulic circuit.
20. Tighten the RIGHT REAR hydraulic wheel circuit bleeder valve securely.
21. Install a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve, then repeat steps 9-14.
22. Install a proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve, then repeat steps 9-14.
23. Install a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve, then repeat steps 9-14.
24. After completing the final wheel hydraulic circuit bleeding procedure, tighten all of the wheel hydraulic circuit bleeder valves and install the bleeder valve dust caps.
25. Close the brake pressure bleeder fluid tank valve.
26. Remove the brake pressure bleeding equipment from the vehicle.
27. Fill the brake master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Refer to «Fluid and Lubricant Recommendations»(/buick/encore/i-2012-2016/remont/lubrication-system/#maintenance-and-lubrication__fluid-and-lubricant-recommendations) .
28. Slowly press and release the brake pedal. Observe the brake pedal feel.
29. If the brake pedal feels spongy, perform the following procedure. If equipped with antilock brakes, install a scan tool and perform the «Antilock Brake System Automated Bleed»(/buick/encore/i-2012-2016/remont/anti-locktraction-control/#antilock-brake-system) to remove air which may be trapped in the BPMV. Inspect the hydraulic brake system for external leaks. Refer to «Brake System External Leak Inspection»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system__brake-system-external-leak-inspection) . Repeat the Bleeding the Complete Brake Hydraulic System procedure.
30. If the brake pedal still feels spongy, pressure bleed the hydraulic brake system. Refer to «Hydraulic Brake System Bleeding (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
31. Turn the ignition switch ON with the engine OFF. Check to see if the brake system warning lamp remains illuminated.
32. If the brake system warning lamp remains illuminated, refer to «Diagnostic Starting Point - Vehicle»(/buick/encore/i-2012-2016/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-starting-point-vehicle) .

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 and/or 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»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) «Front Brake Hose Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) «Rear Brake Hose Replacement (Drum Brake)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Rear Brake Hose Replacement (Disc Brake)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) «Front Brake Caliper Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#disc-brake-system) «Rear Brake Caliper Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#disc-brake-system) , if equipped «Rear Brake Cylinder Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#drum-brake-system) , if equipped «Brake Proportion Valve Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , if equipped «Brake Pressure Modulator Valve Replacement»(/buick/encore/i-2012-2016/remont/anti-locktraction-control/#antilock-brake-system) , if equipped Clean out all the hydraulic brake pipes using denatured alcohol. 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»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) ; also perform the following: Clean the brake master cylinder reservoir using denatured alcohol, 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»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) . «Front Brake Hose Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) «Rear Brake Hose Replacement (Drum Brake)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Rear Brake Hose Replacement (Disc Brake)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) «Front Brake Caliper Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#disc-brake-system) «Rear Brake Caliper Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#disc-brake-system) , if equipped «Rear Brake Cylinder Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#drum-brake-system) , if equipped «Brake Proportion Valve Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , if equipped «Brake Pressure Modulator Valve Replacement»(/buick/encore/i-2012-2016/remont/anti-locktraction-control/#antilock-brake-system) , if equipped
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 which 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 GM approved brake fluid from a clean, sealed brake fluid container.
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 (Manual)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) , «Hydraulic Brake System Bleeding (Pressure)»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

1. With the engine OFF, apply and release the brake pedal several times until the pedal becomes firm to deplete the power vacuum brake booster vacuum reserve.
2. Remove the battery tray. Refer to «Battery Tray Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
3. Disconnect the power vacuum brake booster vacuum sensor electrical connector, if equipped.
4. Remove the power brake booster vacuum check valve (1) from the power vacuum brake booster.
5. Remove the driver side instrument panel knee bolster. Refer to «Instrument Panel Knee Bolster Replacement (Encore)»(/buick/encore/i-2012-2016/remont/exteriorinterior-trim/#instrument-panel-trim-and-console-trim) , «Instrument Panel Knee Bolster Replacement (Trax)»(/buick/encore/i-2012-2016/remont/exteriorinterior-trim/#instrument-panel-trim-and-console-trim) .
6. Compress the tabs on the top and bottom of the brake booster pushrod retainer (1) and lift the brake pedal (2) rearward to disconnect the brake pedal from the power brake booster pushrod.
7. Inspect the brake booster pushrod retainer for damage and replace, if necessary.
8. Remove the master cylinder. Refer to «Master Cylinder Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
9. If equipped with antilock brakes, disconnect the front and rear brake pipe fittings (1) from the brake pressure modulator valve (BPMV). Refer to «Brake Pressure Modulator Valve Replacement»(/buick/encore/i-2012-2016/remont/anti-locktraction-control/#antilock-brake-system) .
10. Completely loosen the power vacuum brake booster bolts (1).
11. Remove the power vacuum brake booster.
12. Inspect the power vacuum brake booster gasket for damage and replace, if necessary.

1. Install the power vacuum brake booster gasket, if removed.
2. Install the power vacuum brake booster and bolts.
3. Install the power vacuum brake booster bolts (1) and tighten to 19 N.m (14 lb ft).
4. If equipped with antilock brakes, connect the front and rear brake pipe fittings (1) to the BPMV. Refer to «Brake Pressure Modulator Valve Replacement»(/buick/encore/i-2012-2016/remont/anti-locktraction-control/#antilock-brake-system) .
5. Install the master cylinder. Refer to «Master Cylinder Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
6. Install the power brake booster vacuum check valve (1) to the power vacuum brake booster.
7. Connect the power vacuum brake booster vacuum sensor electrical connector, if equipped.
8. Install the power brake booster pushrod retainer (1) to the power brake booster pushrod, if removed.
9. Position the brake pedal (2) to the power brake booster pushrod retainer and firmly seat the brake pedal to the retainer.
10. Install the driver side instrument panel knee bolster. Refer to «Instrument Panel Knee Bolster Replacement (Encore)»(/buick/encore/i-2012-2016/remont/exteriorinterior-trim/#instrument-panel-trim-and-console-trim) , «Instrument Panel Knee Bolster Replacement (Trax)»(/buick/encore/i-2012-2016/remont/exteriorinterior-trim/#instrument-panel-trim-and-console-trim) .
11. Install the battery tray. Refer to «Battery Tray Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .

1. With the engine OFF, apply and release the brake pedal several times to deplete the power vacuum brake booster vacuum reserve.
2. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
3. Through the left front wheelhouse, disconnect the power brake booster vacuum hose quick connect (1) from the power brake booster pump port.
4. Lower the vehicle.
5. Disconnect the power brake booster vacuum hose quick connect (1) from the intake manifold vacuum port.
6. Disconnect the power brake booster vacuum sensor electrical connector.
7. Remove the power brake booster vacuum sensor and hose assembly (1) from the power vacuum brake booster grommet.
8. Release the clamp and remove the power brake booster vacuum sensor (1).
9. Remove the power brake booster vacuum hose assembly.

1. Install the power brake booster vacuum hose assembly to the vehicle.
2. Release the clamp and install the power brake booster vacuum sensor (1).
3. Install the power brake booster vacuum sensor and hose assembly (1) to the power vacuum brake booster grommet.
4. Connect the power brake booster vacuum sensor electrical connector.
5. Connect the power brake booster vacuum hose quick connect (1) to the intake manifold vacuum port.
6. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
7. Through the left front wheelhouse, connect the power brake booster vacuum hose quick connect (1) to the power brake booster pump port.

1. With the engine OFF, apply and release the brake pedal several times until the brake pedal becomes firm to deplete the power brake booster vacuum reserve.
2. Remove the battery tray. Refer to «Battery Tray Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
3. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
4. Through the left front wheehouse, disconnect the power brake booster vacuum hose quick connect (1) from the power brake booster pump port.
5. Lower the vehicle.
6. Disconnect the power brake booster pump electrical connector.
7. Release the power brake booster pump vent hose and grommet (1) from the left side rail.
8. Remove the power brake booster pump bracket nuts (1).
9. Remove the power brake booster pump assembly.
10. If replacing the power brake booster pump, remove the power brake booster pump bracket. Refer to «Power Brake Booster Pump Bracket Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

1. Install the power brake booster pump bracket, if removed. Refer to «Power Brake Booster Pump Bracket Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
2. Install the power brake booster pump assembly.
3. Install the power brake booster pump bracket nuts (1). 5 speed manual transmission: Tighten the nuts to 58 (43 lb ft) 6 speed automatic transmission, 6 speed manual transmission: Tighten the nuts to 22 (16 lb ft)
4. Install the power brake booster pump vent hose and grommet (1) to the left side rail.
5. Connect the power brake booster pump electrical connector.
6. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
7. Through the left front wheelhouse, connect the power brake booster vacuum hose quick connect (1) to the power brake booster pump port.
8. Install the battery tray. Refer to «Battery Tray Replacement»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .

1. Remove the power brake booster pump assembly. Refer to «Power Brake Booster Pump Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .
2. Disconnect the power brake booster pump vent hose (1).
3. Release the power brake booster pump electrical harness and retainer from the power brake booster pump bracket.
4. Remove the power brake booster pump nuts (1).
5. Remove the power brake booster pump bolts (1).
6. Remove the power brake booster pump bracket.

1. Install the power brake booster pump bracket to the power brake booster pump.
2. Install the power brake booster pump bolts (1).
3. Install the power brake booster pump nuts (1) and tighten to 7 (62 lb in).
4. Connect the power brake booster pump vent hose (1).
5. Install the power brake booster pump electrical harness and retainer to the power brake booster pump bracket.
6. Install the power brake booster pump. Refer to «Power Brake Booster Pump Replacement»(/buick/encore/i-2012-2016/remont/mechanical-hydraulic/#hydraulic-brake-system) .

System Component Description

The brake assist system consists of the following

System Operation

Under normal driving conditions, without the brakes applied, vacuum is allowed to act on both sides of the diaphragm within the vacuum brake booster. When the brake pedal is applied, the effort by the driver is multiplied due to the relative length of the brake pedal in relationship to its pivot point and the point at which the push rod to the vacuum brake booster is attached.

Movement of the push rod causes a valve within the vacuum brake booster to close between the two sides of the diaphragm, thus isolating each side. It also allows a valve to open that allows atmospheric pressure to act on the pedal side of the vacuum brake booster while maintaining vacuum on the vacuum source side of the diaphragm. The movement of the brake pedal pushrod is transferred to the hydraulic brake master cylinder via the vacuum brake booster. The pressure differential within the vacuum brake booster reduces the effort required by the driver in applying the brakes.

Scheme 3

In order to assure that vacuum is available to the vacuum brake booster, the car can contain a vacuum pump either in addition to the normal intake manifold vacuum source or as stand-alone. The pump provides negative pressure when the engine cannot properly accommodate the requirement, e.g. cold start, heavy throttle, high altitude and turbo pressure.

Scheme 4

The purpose of the brake warning system is to warn the driver of the park brake being applied while the vehicle is being driven, a brake electronic brake distribution (EBD) failure and/or a low brake fluid level condition.

1. When the ignition switch in the ON position and park brake is applied, the brake warning indicator lamp is illuminated. While the ignition switch is turned to the ON position, the battery voltage is provided to the brake warning indicator on the instrument panel cluster (IPC). When the park brake is applied, the park brake switch is grounded and the brake warning indicator is illuminated.
2. EBCM monitors the EBD system. If EBCM detects EBD failure condition, EBCM sends a signal to IPC and IPC illuminates the brake warning indicator.
3. Brake fluid level indicator switch is negative thermal coefficient (NTC) type. When the brake fluid level is too low, the brake warning indicator is illuminated by being grounded through the brake fluid level indicator switch.

The hydraulic brake system consists of the following

Hydraulic output pressure is distributed from the master cylinder through two hydraulic circuits, supplying diagonally-opposed wheel apply circuits.

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 brake linings against rotating brake system components.

Special Tools

Illustration Tool Number/ Description CH 28662 J 28662 Brake Pedal Effort Gauge CH 29532 J 29532 Diaphragm Pressure Bleeder CH 35589-A CH 44894-A J 35589-A J 44894-A Brake Bleeder Adapter CH 45405 J 45405 Brake Pipe Flaring Kit

Scheme 5

Scheme 6

Scheme 7

Scheme 8

See also:
• Diagnostic System Check - Vehicle
• Strategy Based Diagnosis
• Diagnostic Procedure Instructions
• Symptom Byte List
• WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE
• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Control Module References
• Diagnostic Repair Verification
• Diagnostic Trouble Code (DTC) List - Vehicle
• ABS Description and Operation
• Checking Aftermarket Accessories
• Relay Replacement (Within an Electrical Center)
• Relay Replacement (Attached to Wire Harness)
• Parking Brake Indicator Switch Replacement
• Park Brake System Diagnosis (Drum Brake)
• Park Brake System Diagnosis (Disc Brake)
• Symptoms - Suspension General Diagnosis
• Symptoms - Power Steering System
• Brake Pad Inspection
• Front Disc Brake Pads Replacement
• Front Wheel Drive Shaft Outer Joint and Boot Replacement
• Front Disc Brake Mounting and Hardware Inspection
• Brake Rotor Thickness Measurement
• Brake Rotor Thickness Variation Measurement
• Brake Rotor Surface and Wear Inspection
• Brake Rotor Refinishing
• Front Brake Rotor Replacement
• Brake Rotor Assembled Lateral Runout Measurement
• Brake Rotor Assembled Lateral Runout Correction
• Brake Drum Replacement
• Rear Brake Cylinder Replacement
• Drum Brake Hardware Inspection
• Brake Drum Diameter Measurement
• Brake Drum Surface and Wear Inspection
• Brake Drum Refinishing
• Drum Brake Adjustment
• Drum Brake Adjusting Hardware Inspection
• Lifting and Jacking the Vehicle
• Tire and Wheel Removal and Installation
• Diagnostic Starting Point - Vehicle
• Brake Fluid Irritant Warning
• Brake Fluid Effects on Paint and Electrical Components Caution
• Battery Replacement
• Fastener Caution
• Steering Column Replacement (Mexico, N40)
• Brake Pedal Position Sensor Replacement
• Clutch Pedal Position Sensor Replacement
• Accelerator Pedal Position Sensor Replacement
• Brake Dust Warning
• Fluid and Lubricant Recommendations
• Instrument Panel Knee Bolster Replacement (Encore)
• DTC C0267
• Brake Fluid Loss
• Brake Pulsation
• Brake System Noise
• Brake Pedal Excessive Travel
• Brake Pedal Excessive Effort
• Brakes Drag
• Brake System Slow Release
• Brake Assist System Diagnosis
• Symptoms - Hydraulic Brakes
• Brake Pedal Travel Measurement and Inspection
• Brake Pedal Pushrod Inspection
• Brake Pipe Replacement
• Master Cylinder Reservoir Filling
• Brake Pipe and Hose Inspection
• Brake System Internal Leak Test
• Brake System Vacuum Source Test
• Special Tools
• Brake System External Leak Inspection
• Master Cylinder Bench Bleeding
• Fastener Tightening Specifications