The BMW 5 Series ABS pump on Pacific Automotive Network is on the left. Since the BMW 5 Series ABS pump is installed below the A-pillar floor and above the lower body guard on the left side, it may be that the drainage water from the top of the pump flows to it. It could also be that the water on the wheel below is thrown up.
1. The origin of the ABS system. In 1920, the British Honer Moore developed the invention and applied for a patent; in 1936, the German Bosch Company obtained the ABS patent; in 1951, Goodyear Airlines installed it on a truck; in 1954 Ford installed Air France's ABS device on Lincoln cars; in 1978, Bosch and Mercedes-Benz collaborated to develop a three-channel, four-wheel ABS system with digital controllers, laying the foundation and basic model of the ABS system, and mass production Installed on Mercedes-Benz vehicles; in 1981, the German WABCO Company and Mercedes-Benz Company installed digital ABS systems on trucks; in 1984, the ABS/ASR2U brake system with anti-lock braking and drive anti-skid was launched.
2. The role of the ABS system. The Chinese name of the ABS system (antilockbrakesystem) is the anti-lock brake system. As the name suggests, the ABS system prevents the car's tires from locking when braking. If the tires lock, the vehicle will lose control of the direction, which can easily cause serious consequences.
3. Advantages of ABS system
1. Reduce braking distance;
2. Reduce floating phenomenon;
3. Enhance Control of vehicles;
4. Reduce local tire wear.
As you can see from the picture, the braking marks of vehicles with ABS are intermittent.
4. The composition of the ABS system. The ABS system mainly installs three parts: sensor (wheel speed sensor), controller (ABS-ECU) and actuator (ABS pump) on the original braking system. .
Click to view more details about the composition and structure of the ABS system. Next, let’s talk about content that is not in the above article.
5. Wheel speed sensor. The wheel speed sensor is mainly a magnetic pulse type. sensor. There are two wires and three wires. The three wires have an extra signal shielding wire.
Each tire has a wheel speed sensor that monitors the speed of each wheel and converts the wheel speed signal into an electronic signal and provides it to the ECU computer. The ECU then controls the hydraulic regulator to work based on this signal. Faults:
1. The signal rotor is deformed, detached, worn, or cracked. Replace the signal rotor. (Some cars use magnetically encoded bearings to replace the signal rotor)
2. The sensor probe is dirty or damaged. Replace the sensor
3. The sensor coil is open or short-circuited. Replace the sensor
4. The sensor harness is open or short-circuited. Replace the sensor (with harness) or repair the circuit. Note: The gap between the sensor and the signal plate is about 0.25~0.45mm.
Detection:
1. The most commonly used detection method is to report a tire sensor failure. Switch the left and right sides and then read the fault code. If it is still on the original side, it is If the line is faulty, if it is switched to the other side, it is a sensor fault.
2. Measure the resistance with a multimeter; (rarely used)
3. Measure the signal with a multimeter or test light. (Rarely used)
6. ABS pump consists of: DC motor, hydraulic pump, solenoid valve, pressure accumulator, liquid reservoir, etc.