
The bleeding sequence is: right rear wheel, left front wheel, left rear wheel, right front wheel. Unscrew the reservoir cap and fill it with brake fluid. Be careful not to spill brake fluid on the paintwork. If any spills occur, clean it immediately. Connect the bleed to the brake wheel cylinder's bleed port, with the other end inserted into a container holding some brake fluid. Connect the Hi-Scan diagnostic tool's plug to the diagnostic socket. Press the "YES" key to operate the return pump rotation and close the solenoid valve. Press the "YES" key to begin bleeding. Note: The motor should not run for more than 60 seconds to prevent damage.

I've replaced the ABS pump myself, and bleeding it is quite particular. First, install the new pump, connect the diagnostic tool to activate the ABS self-bleeding function, letting the pump run on its own to remove internal air. Then, prepare brake fluid, a clear , and a container, turn the ignition to the on position without starting the engine. The bleeding sequence is crucial—start with the wheel farthest from the pump: open the bleeder screw on the right rear wheel, attach the tube, have someone help by pressing the brake pedal firmly five or six times, and tighten the screw once no bubbles are seen in the clear tube. Repeat the same steps for the left rear, right front, and left front wheels. Throughout the process, keep topping up with fresh brake fluid to maintain the level at the midpoint. Finally, start the car and press the brake pedal a few times to test its firmness. Last time, I rushed and skipped the right rear, starting with the left front instead, resulting in brakes as soft as stepping on cotton, forcing me to redo the entire bleeding process.

Last time at the repair shop, the mechanic performed the ABS pump bleeding procedure with remarkable efficiency. He connected the diagnostic computer, accessed the system menu, and directly activated the ABS module's hydraulic test function to internally circulate and purge the pump first. Then each wheel was processed in the sequence of right rear, left rear, right front, and left front. The assistant loosened the bleeder screws with a wrench while the master mechanic coordinated brake pedal presses from the driver's seat - transparent tubing first sprayed bubbles before stabilizing into steady fluid flow. After each wheel's bleeding, the brake fluid reservoir level was checked and replenished. Finally, the mechanic used a lift to inspect for potential line leaks. The entire process took under 30 minutes, with the key result being immediately firmer brake pedal feel post-bleeding.

As an auto repair apprentice, my master particularly emphasized the details of ABS pump bleeding. It requires two people to cooperate: one operates the diagnostic device to enter the special function menu and activate the hydraulic cycle, while the other wears gloves and holds a measuring cup to catch the fluid. The bleeder screws must be loosened in a diagonal sequence (right rear, left rear, right front, left front), each time loosening half a turn and waiting for the fluid to flow out. The key is to tighten the screws only when, under the command to press the brake, the bubbles in the disappear and the fluid flows continuously for two seconds. Throughout the process, ensure the fluid level in the reservoir does not drop below the MIN line. The first time I did it, I forgot to top up the fluid, resulting in air entering the system. Finally, during the test, my master had me start the engine while holding the brake pedal, and the pedal had to sink half a finger's width for the procedure to be considered successful.

From a safety-first perspective, incomplete ABS pump bleeding can be life-threatening. Before bleeding, ensure the vehicle is turned off but powered on, and use a diagnostic tool connected to the OBD port to activate the pump circulation function for at least 30 seconds. The key is to bleed the wheels in the correct order: start with the right rear wheel (usually it has the longest hydraulic line), followed by the left rear, right front, and left front wheels. During each wheel's operation, have an assistant continuously press and release the brake pedal over a dozen times until no air bubbles are visible in the transparent tube's fluid flow. Always use brake fluid that meets the original manufacturer's specifications, as mixing old and new fluid can corrode the seals. After completing the process, test-drive to check for the ABS engagement's pulsation; otherwise, residual air can increase braking distance, making emergency stops on icy surfaces particularly hazardous.

The ABS pump bleeding principle is to remove air bubbles from the hydraulic lines. First, use a diagnostic tool to activate the automatic bleeding mode and run the pump motor to expel gas from the pump chamber. Then proceed with manual operation: loosen the bleeder screws in the order of right rear → left rear → right front → left front (most vehicles' hydraulic circuit design places the right rear wheel farthest from the pump). Connect a drain from each wheel to an oil container and have an assistant repeatedly press and release the brake pedal at least eight times. A crucial detail is to press the brake pedal quickly and firmly, then release it slowly, ensuring suction can dislodge trapped air bubbles. The entire process consumes at least 1 liter of fresh brake fluid. After completion, always check all four wheel bleed ports for leaks to prevent subsequent brake fluid loss.


