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Dynamic Ride Control, Checking System Pressure






Dynamic Ride Control, Checking System Pressure

Special tools, testers and auxiliary items required

Charging Device (V.A.S 6209/2)

Hand Vacuum Pump (VAS 6213)

Bleed Charging Device (V.A.S 6209/2 )

Use only approved oil for the bleeding procedure.

Charging Device (V.A.S 6209/2) must always be bled at initial use.

If Charging Device (V.A.S 6209/2) still shows a residual pressure greater than 0.5 bar (e.g. from a previous reading), bleeding must not be done.

- To bleed pressure gauge - B - and line section - A -, install special tool as shown in illustration.





Illustration shows bleeding process by extracting hydraulic oil with Hand Vacuum Pump (VAS 6213)

- Bleed process must be performed until air bubbles are no longer visible in hose - C -.

- Disconnect hose - C - and - D - and perform system pressure check.

System pressure check is performed on front shock absorber of corresponding DRC line.

To attach or detach Charging Device (V.A.S 6209/2 ), system line to be checked must be locked at central valve to limit the quantity of oil leaked to a minimum and to prevent pressurized central valve from emptying.

- Remove wheel.

- Remove plastic cover - 1 -.





- Loosen lock nut - 1 - on line to be checked, screw in shut-off screw - 2 - until it is hand tight and lock nut - 1 - again.





- Remove dust cap and connect Charging Device ( V.A.S 6209/2).





- Loosen lock nut - 1 - on line to be checked, unscrew shut-off screw - 2 - until it is hand tight and lock nut - 1 - again.





- Read system pressure at Charging Device (V.A.S 6209/2).





Pressure increase at Charging Device (V.A.S 6209/2 ) occurs slowly and takes approximately 2 minutes. DRC system pressure can only be read when Charging Device (V.A.S 6209/2) needle has finally come to a stop.

- Disconnect Charging Device (V.A.S 6209/2) and install dust cap.





Small oil leak which results from connecting or disconnected Charging Device (V.A.S 6209/2) at connection is not critical. Avoid repeating measurements because a small quantity of oil is removed from the system every time Charging Device (V.A.S 6209/2) is connected. Every connection results in a pressure decrease of approximately 0.3 bar from the previous reading. Multiple repeated measurements decrease system pressure below minimum pressure or failure, which then requires a replacement of central valve of respective DRC line.

- If the pressure is not OK, determine the cause and service the system.

- Install the plastic cover - 1 -.





DRC system pressure values

Pressure values refer to reference temperature of 20 °C.

16 bar = maximum pressure

15 bar - 16 bar = central valve new or as good as new

12 - 15 bar = normal range of operation, system OK

< 12 bar = system leaking or not filled completely, air entering system, central valve has no pressure/is empty.