Chevrolet Equinox Service Manual: Hydraulic Brake System Bleeding (Pressure) Hydraulic Brakes

Warning:Refer toBrake Fluid Irritant Warning.

Caution:Refer toBrake Fluid Effects on Paint and Electrical Components Caution.

Caution:Only use products that comply with GM specifications andcheck manufacturer information respectively. We recommend the useof GM genuine products. Instructions must be followed at all times.The use of any type of fluid other than the recommended type ofbrake fluid, may cause contamination which could result in damageto the internal rubber seals and/or rubber linings of hydraulicbrake system components.

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

Bleeding a Single Hydraulic Brake CircuitWith the ignition OFF and the brakes cool, apply the brakes 3–5-times, or until thebrake pedal effort increases significantly, in order to deplete the brake boosterpower reserve.Place a clean shop cloth beneath the brake master cylinder to catch brake fluid spills.Clean the outside of the reservoir on and around the reservoir cap prior to removingthe cap and diaphragm.Fill the brake master cylinder reservoir to the maximum-full level with GM approvedbrake fluid from a clean, sealed brake fluid container. Refer toFluid and Lubricant Recommendations.

Note:The pressure bleeding equipment must be the diaphragm type. The rubber diaphragmbetween the air supply and the brake fluid prevents air, moisture, oil, and othercontaminants from entering the hydraulic system.

Following the brake pressure bleeder manufacturer's instructions, fill the brake pressurebleeder with GM approved brake fluid from a clean, sealed brake fluid container.Install the appropriate master cylinder reservoir adapter and connect the brake pressurebleeder.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.Open the brake pressure bleeder fluid tank valve to allow pressurized brake fluidto enter the brake hydraulic system.

Note:Any brake fluid leaks identified require repair prior to completing this procedure.

Wait approximately-30-seconds, then inspect the entire hydraulic brake system forexternal brake fluid leaks.Install a proper box-end wrench onto the wheel hydraulic circuit bleeder valve whichhas been serviced.Install a transparent hose over the end of the bleeder valve.Submerge the open end of the transparent hose into a transparent container partiallyfilled with brake fluid from a clean, sealed brake fluid container.Loosen the bleeder valve to purge air from the wheel hydraulic circuit.Allow fluid to flow until air bubbles stop flowing from the bleeder.After all air has been purged from the hydraulic circuit, tighten the bleeder valveand install the dust cap.

Note:The brake reservoir may have residual pressure after the bleeding operation is complete.Wrap a clean shop towel around the bleeder adapter and all hose connections beforedisconnecting the pressure bleeding equipment to prevent brake fluid from contactingand damaging vehicle components and painted surfaces.

Close the brake pressure bleeder fluid tank valve then disconnect the brake pressurebleeder from the master cylinder reservoir bleeder adapter.Remove the master cylinder reservoir bleeder adapter from the master cylinder reservoir.Fill the brake master cylinder reservoir to the maximum-fill level with GM approvedbrake 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, perform the Bleeding the Complete Brake HydraulicSystem procedure:Turn the ignition key ON, with the engine OFF. Check to see if the brake system warninglamp remains illuminated.

Note:DO NOT allow the vehicle to be driven until it is diagnosed and repaired.

If the brake system warning lamp remains illuminated, refer toDiagnostic Starting Point - Vehicle.Bleeding the Complete Brake Hydraulic SystemWith the ignition OFF and the brakes cool, apply the brakes 3–5-times, or until thebrake pedal effort increases significantly, in order to deplete the brake boosterpower reserve.Place a clean shop cloth beneath the brake master cylinder to catch brake fluid spills.Clean the outside of the reservoir on and around the reservoir cap prior to removingthe cap and diaphragm.Fill the brake master cylinder reservoir to the maximum-full level with GM approvedbrake fluid from a clean, sealed brake fluid container. Refer toFluid and Lubricant Recommendations.If the master cylinder was replaced, the master cylinder must be bench bled. RefertoMaster Cylinder Bench Bleeding.If the brake pipes have been removed from the master cylinder, the following stepsmust be performed.With the rear brake pipe installed securely to the master cylinder, loosen and separatethe 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 mastercylinder. 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 cylinderand tighten the fitting.Have an assistant slowly press the brake pedal fully and maintain steady pressureon the pedal.Loosen the front brake pipe fitting from the front port of the brake master cylinderto purge air from the master cylinder port.Tighten the front brake pipe fitting, then have the assistant slowly release the brakepedal.Wait-15-seconds, then repeat steps-6.4-6.6-until all air is purged from the frontbrake pipe fitting of the front port of the master cylinder.After all air is purged from the front port of the brake master cylinder, tightenthe front master cylinder brake pipe fitting. Refer toFastener Tightening Specifications.With the front brake pipe fitting installed securely to the front port of the brakemaster cylinder, loosen and separate the rear brake pipe fitting from the rear portof 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 therear master cylinder brake pipe fitting. Refer toFastener 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.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 mustbe purged from each port of the respective assembly beginning with the feed pipesfrom the master cylinder.Loosen and separate one of the master cylinder brake pipe fittings from the inletport 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 pressureon 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 brakepipe 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 onthe assembly. Refer toFastener Tightening Specifications.Fill the master cylinder reservoir to the maximum-full level with GM approved brakefluid 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.

Note:The pressure bleeding equipment must be the diaphragm type. The rubber diaphragmbetween the air supply and the brake fluid prevents air, moisture, oil, and othercontaminants from entering the hydraulic system.

Following the brake pressure bleeder manufacturer's instructions, fill the brake pressurebleeder with GM approved brake fluid from a clean, sealed brake fluid container.Install the appropriate master cylinder reservoir adapter and connect the brake pressurebleeder.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.Open the brake pressure bleeder fluid tank valve to allow pressurized brake fluidto enter the brake hydraulic system.

Note:Any brake fluid leaks identified require repair prior to completing this procedure.

Wait approximately-30-seconds, then inspect the entire hydraulic brake system forexternal brake fluid leaks.Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleedervalve.Install a transparent hose over the end of the bleeder valve.Submerge the open end of the transparent hose into a transparent container partiallyfilled with GM approved brake fluid from a clean, sealed brake fluid container.Have an assistant slowly press the brake pedal fully and maintain steady pressureon the brake pedal.Loosen the bleeder valve to purge air from the wheel hydraulic circuit.Tighten the bleeder valve, then have the assistant slowly release the brake pedal.Wait-15-seconds, then repeat steps-11-13-until all air is purged from the wheel hydrauliccircuit.Tighten the RIGHT REAR hydraulic wheel circuit bleeder valve securely.Install a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleedervalve, then repeat steps-9-14.Install a proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleedervalve, then repeat steps-9-14.Install a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleedervalve, then repeat steps-9-14.After completing the final wheel hydraulic circuit bleeding procedure, tighten allof the wheel hydraulic circuit bleeder valves and install the bleeder valve dust caps.Close the brake pressure bleeder fluid tank valve.

Note:The brake reservoir may have residual pressure after the bleeding operation is complete.Wrap a clean shop towel around the bleeder adapter and all hose connections beforedisconnecting the pressure bleeding equipment to prevent brake fluid from contactingand damaging vehicle components and painted surfaces.

Remove the brake pressure bleeding equipment from the vehicle.Fill the brake master cylinder reservoir to the maximum-full level with GM approvedbrake fluid from a clean, sealed brake fluid container. Refer toFluid and Lubricant Recommendations.Slowly press and release the brake pedal. Observe the brake pedal feel.If the brake pedal feels spongy, perform the following procedure.If equipped with antilock brakes, install a scan tool and perform theAntilock Brake System Automated Bleedto remove air which may be trapped in the BPMV.Inspect the hydraulic brake system for external leaks. Refer toBrake System External Leak Inspection.Repeat the Bleeding the Complete Brake Hydraulic System procedure.If the brake pedal still feels spongy, pressure bleed the hydraulic brake system.Refer toHydraulic Brake System Bleeding.Turn the ignition switch ON with the engine OFF. Check to see if the brake systemwarning lamp remains illuminated.

Note:DO NOT allow the vehicle to be driven until the brake system is diagnosed and repaired.

If the brake system warning lamp remains illuminated, refer toDiagnostic Starting Point - Vehicle.