The Volkswagen Polo / Vento ABS pump is an essential part of the car’s Anti-lock Braking System (ABS). Its main function is to regulate hydraulic brake pressure during emergency or hard braking to prevent wheel lock-up and maintain steering control.

Description:

• Component: ABS Hydraulic Unit (ABS Pump + Control Module)
• Location: Mounted in the engine bay, usually near the brake master cylinder.
• Structure:
  
• Electric motor pump generates and regulates hydraulic pressure.
• Valve block (hydraulic modulator) contains solenoid valves to control brake fluid flow to each wheel.
• Electronic control module (ECU) processes wheel speed sensor signals and controls the solenoid valves and pump.
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• Operation:
  
• Wheel speed sensors detect if any wheel is about to lock.
• The ABS ECU activates the pump and solenoid valves.
• Brake fluid pressure is modulated (increase, hold, release) to keep wheels rotating under braking.
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• Extra Functions (depending on variant): May also support EBD (Electronic Brakeforce Distribution), ESC (Electronic Stability Control), and TCS (Traction Control System).

Common Part Numbers (varies by year/model):

• 6R0 614 517
• 6C0 614 517
• 6R0 907 379 (ECU module)

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