What Causes the ABS Pump to Keep Making Noise?

[McMicah]

ABS pump continuously making noise is caused by an internal control short circuit in the ABS pump. Below are the specific details about the ABS system: 1. Function of the ABS System: ABS stands for Anti-lock Braking System, which is part of the vehicle's active safety systems. When the ABS light comes on, it indicates that the vehicle's computer has detected a fault in the ABS system. 2. Principle of the ABS Light: Under normal driving conditions, the ABS remains in a dormant state. It only activates during emergency braking, such as when braking hard at high speeds. The vehicle's computer determines when the ABS should intervene. When the ABS light comes on, it is often due to the wheel speed sensors not functioning properly. The ABS computer cannot detect the driving conditions of each wheel, making it impossible to compare the slip amounts of the wheels, which results in the ABS system failing to operate correctly.

[OAngela]

That day, the ABS pump in my car suddenly kept buzzing non-stop, which was really annoying. Actually, this kind of continuous noise is most commonly caused by a dirty or faulty wheel speed sensor, especially when driving in the rain and mud splashes onto the sensor, causing the ABS pump to keep working stupidly. Additionally, aging relays in the ABS pump itself can also cause the motor to keep running—I’ve personally seen this during a disassembly at the repair shop, where the relay contacts were burnt black. Loose wiring connections or water ingress can also cause a short circuit, making the pump spin wildly. Sometimes, the control module might malfunction and send erratic commands. To fix it, try turning off the engine and waiting for ten minutes to see if it resets. If that doesn’t work, quickly go get a diagnostic tool to read the fault codes—don’t delay, as it might affect braking sensitivity.

[HaileyDella]

My ABS pump was also buzzing non-stop since last week, humming continuously right after startup. Initially thought the brake pads were worn out, but after lifting the car, all four wheel sensors were clean and properly positioned. The mechanic used a pressure gauge to test the pump and found unstable brake fluid pressure causing the pump to cycle repeatedly. Refilling with genuine DOT4 brake fluid fixed it. Such issues could also be caused by worn wheel hub bearings generating extra signal interference, or mismatched aftermarket parts from the last replacement. Remember if the dashboard warning light flashes simultaneously, it indicates the system entered protection mode and requires immediate attention.

[LaJasper]

The continuous operation of the ABS pump mainly involves three aspects: signal reception errors such as sensor failure, abnormal calculations by the control unit, or motor jamming in the actuator. Simply put, the car misjudges tire slippage and works excessively. Key checks include ensuring consistent tire pressure, inspecting the wheel speed sensor magnetic rings for oil contamination, and checking for corrosion in grounding wires. Upgrading to oversized rims may also disrupt the original signal frequency, triggering this issue. Timely inspection is crucial.