Vacuum Pump: Description and Operation

Electric Brake Vacuum Pump

Description and function

Vacuum pump has On Board Diagnostic (OBD) properties. Detected faults are stored in engine control module.

Electric vacuum pump function check can only be carried out using OBD with engine off!

Special tools, testers and auxiliary items required

• Vehicle Diagnosis, Testing And Information System (VAS 5051)

• Diagnostic Cable (VAS 5051/1) or diagnostic cable (VAS 5051/3)

Procedure

- With the ignition switched off, connect the Vehicle Diagnostic, Test and Information System (VAS 5051) with the diagnostic cable (VAS 5051/1) or Diagnostic Cable (VAS 5051/3) to the diagnostic connection.

- Switch on tester - arrow -.





The tester will now require up to 3 minutes to boot up.

- Switch on ignition.

- Select operating mode: On the display, select "Vehicle On-Board Diagnosis".

- Select vehicle system: Select "Engine Electronics".

At the upper right of the screen, the control module identification and coding are displayed.

- Select diagnostic function: At this point, all diagnostic functions are available.

- On the display, select "006 - Basic setting".

- Press 0, 1 and 1 measured values block.

- Confirm input with Q button.

Displayed at the bottom of the screen:





- Actuate the brake pedal multiple times with consistent force until the test activates.

Displayed at the bottom of the screen:





The brake pedal may no longer be actuated once the test begins.

The Brake System Vacuum Pump (V192) supplies the brake booster with vacuum. At the same time, the control module performs a diagnosis of the brake booster system.

If the pressure within in the brake booster reaches the cut-off threshold by the time that was predetermined by the diagnostic function, the test has been passed.

Displayed at the bottom of the screen:





- Using the Go to button, the operating mode can be interrupted or ended.

If the pressure within in the brake booster does not reach the cut-off threshold by the time that was predetermined by the diagnostic function, the test has been failed.

Displayed at the bottom of the screen:





- Perform "Guided Fault Finding" with the Vehicle Diagnosis, Testing and Information System (VAS 5051).