Critical failure of the braking system, manifested by uncontrolled, continuous operation of the ABS pump motor, mainly affects vehicles equipped with the Bosch ATE TRW system. This is a specific failure in which the module's electric motor runs (characteristically "hums") even after the ignition is turned off and the key is removed from the ignition.
Because the pump executive circuit is powered directly from the battery, the damaged controller is unable to cut off the voltage, which leads to the device operating in continuous mode.
Cause of fault: Degradation of the electrical harness and short circuit
Unlike older generations of systems, in the case of ABS pumps, the source of the problem is most often damage to the harness supplying the ABS controller.
This external short circuit generates current or voltage pulses that permanently damage the actuators inside the ABS controller (usually the so-called relay contacts stick together or the engine control transistors break down). As a result, even after repairing the harness, the controller remains damaged and supplies voltage to the engine continuously.
Professional repair of the Bosch ATE TRW controller
When the control electronics are damaged by a faulty harness, simply repairing the cables is not enough. it is necessary to repair the ABS controller.
Our service specializes in the repair of Bosch ATE and TRW controllers with symptoms of continuous engine operation. The service procedure includes replacing damaged semiconductor and relay elements with components with increased durability. We also verify the electronics for other damage caused by overvoltage.
We recommend sending the damaged module to us. At the same time, we advise you to verify the condition of the vehicle's electrical harness before installing the repaired part to avoid another failure.