For routine brake fluid changes, like prepping for track days or regular car maintenance, a full ABS bleed with a scan tool might not be essential. A standard manual bleed can often suffice for these scenarios. This is because minimal old fluid remains, and any residual fluid unlikely reaches the calipers unless the ABS system is activated post-bleed. In such cases, a recommended bleed sequence is Rear Right, Left Front, Rear Left, and Right Front, aligning with the cross-split brake system layout, unlike older front/rear split systems.
However, an ABS scan tool becomes invaluable if air enters the ABS module itself. The automated bleed procedure with a scan tool is specifically designed to purge air from the ABS module effectively. Regardless of the reason – necessity or simply for thoroughness – initiating the auto bleed sequence on a brake system that hasn’t been fully drained should be adequate. Each time this procedure is executed, a sufficient volume of brake fluid is pushed through, effectively clearing the ABS module, lines, and calipers simultaneously.
Typically, using a scan tool involves a guided, step-by-step process displayed on the scanner screen. This often includes prompts such as “Open Bleed Screw X and pump the brake pedal” for a specified duration, followed by instructions to stop and move to the next brake corner. For front calipers, which often have inner and outer bleed screws, it’s advisable to perform the ABS tool procedure using the inner bleed screw. Subsequently, conducting a couple of manual bleed cycles on the outer screw ensures all areas of the caliper receive fresh fluid. This supplementary manual bleeding can be done between automated bleed cycles if the scan tool permits, or after completing all automated bleeding steps.
