The ABS pump in a Toyota Vios 150 (1.5L engine), model code 1A, is a critical component of the Anti-lock Braking System (ABS). Its main role is to regulate brake fluid pressure to prevent the wheels from locking up during hard braking, thereby maintaining steering control and vehicle stability.

ABS Pump Description:

• Component Name: ABS Pump/Modulator Assembly
• Function: Maintains optimal brake pressure during emergency braking to prevent wheel lock-up.
• System Type: Hydraulic and electronic control (part of the ABS module)
• Location: Usually mounted in the engine bay near the brake master cylinder.
• Main Parts:
  
• Electric motor: Drives the hydraulic pump.
• Hydraulic modulator: Regulates brake fluid pressure using solenoid valves.
• Control unit (ECU): Communicates with wheel speed sensors and controls solenoids based on feedback.
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• Operation: When ABS is activated, the control unit commands the pump to build and release brake pressure rapidly to avoid skidding.

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