Brake Bleeding with VCDS (Solution)

Hello Forum,

I'm new here, and I've been working as a mechanic for several years.

Here's a basic understanding question regarding brake bleeding on a Skoda Fabia 1 ESP:

According to Erwin (siehe Fehlerdatenbank) and Elsa, in addition to the machine ventilation with ~2 bar, the system must also be vented with the scanner (I have VCDS) when
1.: A room in the HBZ is empty.
2.: Generally, the system was open (brake hose or piston new).

Okay, I don't have any of these problems at the moment, but I don't quite understand what Erwin (siehe Fehlerdatenbank) and Elsa want to do with the scanner. There is a note saying, "VA left and right ventilation screws open... both at the same time????
Huh?
And finally, to be able to drain again, just like before???

Something quite opaque.

As I said, I don't have this specific problem, but I just want to know it in general. He who stands still, rusts.

Next, if I normally completely disassemble a saddle or remove a hose, I place a rubber plug over the line, then do I really always have to bleed it using a scanner (VCDS), or is the normal one sufficient?

Thank you in advance for the clarification.

Hello,

"Unfortunately, there are people who believe that 'normal' bleeding is sufficient, even when there is no actual braking performance. Therefore, the ABS - valve block needs to be bled using the control unit."

This is a precautionary measure designed to ensure that there are no hidden air bubbles.

As long as there is no significant loss of brake fluid and the risk of air bubbles spreading throughout the system remains, "normal" bleeding is sufficient.

The additional venting of the valve block CANNOT prevent damage.

In general, after a brake repair, it's advisable to test the system up to the ABS control limit. This way, you (hopefully) can see for yourself whether the system is functioning normally or not. And that is something that MUST be tested BEFORE you have to use it in a real emergency braking situation in road traffic.

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If I normally completely remove a seat or remove a hose, I place a rubber plug over the line, then I really still have to bleed it using a scanner (VCDS)

If you're fast enough, then not really. But who knows if the colleague will not already be preparing a snack and spilling everything out (and thus letting air in) before searching for the stopper?

As I said: Anyone who wants to completely exclude a fault can do so by using the VCDS diagnostic tool. To do this, go to the ABS/ESP control unit (address 03) and, depending on the control unit, select either block 1 or 2 in the basic settings mode. Which one is correct, you can see anyway in VCDS itself.

Best regards, Rainer

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As long as there are no major parts of the braking system that are empty, and thus there is a risk that air bubbles will spread throughout the system, 'normal' bleeding is sufficient.

I see/do the same.

However, if the brake fluid reservoir has truly become empty and air has entered the brake unit, then, in most cases, normal bleeding will hardly be effective...

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There, it says, VA left and right ventilation screws open...both at the same time????

Okay... then the valve block will be activated.
Then you do this a few times and also at the back (although this hasn't yet been achieved with every vas tester ).

Okay, so man braucht 2 Flaschen zum Aufhängen und generell sollte man darauf achten (wenn man es nicht selbst macht), dass tatsächlich 2 bar eingestellt sind. Most people don't know this, but they simply turn the device on regularly.

Therefore, the traditional method of draining by foot is no longer advisable.


Have you ever used devices that vacuum using suction instead of pumping through the HBZ (presumably a type of pump or system)?

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and, in general, it's important to make sure that 2 bars are actually set. Most people don't know this, but they simply turn the device on regularly.

yes... the manufacturer specifies different procedures...

Form:

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ABS Mark 60: To bleed the hydraulic unit on the Mark 60 ABS system, the filling pressure of 1 bar must not be exceeded

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ABS Bosch 5.7 and Bosch 8.0: To bleed the hydraulic unit on the Bosch 5.7 and Bosch 8.0, a filling pressure of 2 bar is required.

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Preliminary discussion: – Turn off the brake filling and bleeding unit –VAS 5234- or –V.A.G 1869- and set the corresponding form on the brake filling and bleeding unit. Ventilation Sequence: 1 - Front left and right brake calipers simultaneously bleed 2 - Simultaneously bleed the rear left and rear right brake calipers. – Keep the vent valves on the attached hoses of the bleeder bottle open until air-free brake fluid flows out. Subsequently, the hydraulic unit should be re-vented using the "Default Settings" function with the VAS 5051 tester. Initial Setup (For Bleeding the Brake System):

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Ventilation (normal): Please strictly adhere to the operating procedure for bleeding the braking system. – Turn off the brake filling and bleeding unit –VAS 5234- or –V.A.G 1869- and set the corresponding form on the brake filling and bleeding unit. – Open the vent valves in the prescribed order and bleed the brake calipers. ABS Mark 60 Venting Sequence: 1 - Front left brake caliper 2 - Front right brake caliper 3 - Rear left brake cylinder/caliper 4 - Rear right brake cylinder/brake caliper Bosch 5.7 and Bosch 8.0 Bleed Sequence: 1 - Rear right brake cylinder/brake caliper 2 - Rear left brake cylinder/brake caliper 3 - Front right brake caliper 4 - Front left brake caliper

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Ventilation To do this, a second {ITEM} is needed. **We are looking for a skilled assembler:** – Press and hold the brake pedal with a high amount of force. – Open the vent on the brake caliper. – Press the brake pedal to the very end. – Close the vent screw when the pedal is depressed. – Slowly release the brake pedal. This bleeding process must be performed 5 times per brake caliper. Ventilation Sequence: 1 - Front left brake caliper 2 - Front right brake caliper 3 - Rear left brake caliper 4 - Rear right brake caliper After venting, a test drive must be performed. "This requires at least one ABS (Anti-lock Braking System) control to be implemented."