- Before servicing the vehicle, refer to the Precautions section.
The base brake-s hydraulic system must be bled anytime air enters the hydraulic system. The ABS must always be bled anytime it is suspected that the HCU has ingested air.
Brake systems with ABS must be bled as two independent braking systems. The non-ABS portion of the brake system with ABS is to be bled the same as any non-ABS system.
The ABS portion of the brake system must be bled separately. Use the following procedure to properly bleed the brake hydraulic system including the ABS.
When bleeding the ABS system, the following bleeding sequence must be followed to insure complete and adequate bleeding.
- Make sure all hydraulic fluid lines are installed and properly torqued.
- Connect the scan tool to the diagnostics connector. The diagnostic connector is located under the lower steering column cover to the left of the steering column.
Using the scan tool, check to make sure the ABM does not have any fault codes stored. If it does, clear them.
CAUTIONWhen bleeding the brake system wear safety glasses. A clear bleed tube must be attached to the bleeder screws and submerged in a clear container filled part way with clean brake fluid. Direct the flow of brake fluid away from yourself and the painted surfaces of the vehicle. Brake fluid at high pressure may come out of the bleeder screws when opened.
- Bleed the base brake system.
- Using a scan tool, select ECU VIEW, followed by ABS MISCELLANEOUS FUNCTIONS to access bleeding. Follow the instructions displayed. When finished, disconnect the scan tool and proceed.
- Bleed the base brake system a second time. Check brake fluid level in the reservoir periodically to prevent emptying, causing air to enter the hydraulic system.
- Fill the master cylinder fluid reservoir to the MAX level.
- Test drive the vehicle to be sure the brakes are operating correctly and that the brake pedal does not feel spongy.