Standard Procedure

The base brake's hydraulic system must be bled anytime air enters hydraulic system. The ABS though, particularly ICU (HCU), should only need to be bled when HCU is replaced or removed from vehicle. The ABS must always be bled anytime it is suspected that HCU has ingested air. Under most circumstances that require bleeding of brakes hydraulic system, only base brake hydraulic system needs to be bled. When bleeding ABS system, following bleeding sequence must be followed to insure complete and adequate bleeding.

1. Make sure all hydraulic fluid lines are installed and properly torqued. Connect DRBIII(R) scan tool to Data Link Connector. The connector is located under lower instrument panel to left of clutch pedal. Using DRBIII(R), check to make sure CAB does not have any fault codes stored. If it does, clear them using DRBIII(R).
   WARNING: When bleeding brake system, wear safety glasses. A clear bleed tube must be attached to bleeder screws and submerged in a clear container filled part way with clean brake fluid. Direct the flow of brake fluid away from your self and painted surfaces of vehicle. Brake fluid at high pressure may come out of bleeder screws when opened.
2. Bleed base brake system using standard pressure or manual bleeding procedure. Using DRBIII(R), select ANTI-LOCK BRAKES, followed by MISCELLANEOUS, then BLEED BRAKES. Follow instructions displayed. When scan tool displays TEST COMPLETED, disconnect scan tool and proceed. Bleed base brake system a second time.
3. Check brake fluid level in reservoir periodically to prevent emptying, causing air to enter hydraulic system. Fill master cylinder reservoir to full level. Test drive vehicle to be sure brakes are operating correctly and that brake pedal does not feel spongy.