Dynamic Ride Control (DRC), Draining And Filling
Extracting, evacuating and filling the whole DRC line (lines/shock absorber and central valve) is performed with the DRC Filling Device :VAS 6544 Depending on the DRC system equipment in the dealership, the equipment may need to be modified or updated with the supplement or retrofit set to match the version of the DRC Filling Device :VAS 6544 . The following choices are possible:
Special tools and workshop equipment required
- Vehicle Diagnostic Tester
- DRC Filling Device :VAS 6209/4
The DRC Filling Device :VAS 6209/4 serves as a retrofit set to the DRC Charging Device :VAS 6209 already found in dealerships.
Special tools and workshop equipment required
- Retrofit Kit, DRC System :VAS 6209/5
The Retrofit Kit, DRC System :VAS 6209/5 is needed if the dealership has the DRC Charging Device, Pressure Pump :VAS 6209/3 and wants to upgrade the DRC Filling Device :VAS 6544 . The DRC System Supplementary Kit :VAS 6209/6 is also necessary.
Special tools and workshop equipment required
- DRC System Supplementary Kit :VAS 6209/6
The DRC System Supplementary Kit :VAS 6209/6 is needed to upgrade the DRC Charging Device, Pressure Pump :VAS 6209/3 to the DRC Filling Device :VAS 6544 . The requirement is that the dealership already has the DRC Charging Device :VAS 6209 . If the dealership does have the DRC Charging Device :VAS 6209 , then the Retrofit Kit, DRC System :VAS 6209/5 must also be obtained.
Special tools and workshop equipment required
- DRC Filling Device :VAS 6544
Required components from the DRC Filling Device :VAS 6544
- Not Required
- Not Required
- Charging Hose with Quick-Release Fastener
- Venturi Injector with Drain Hose
- From the DRC Charging Device :VAS 6209
- Connecting Hose
- From the DRC Charging Device :VAS 6209
- DRC Filling Device :VAS 6544
- Used Oil Container
- empty before starting the work
- Identification: red dot
Updating the equipment for the DRC system must be done one time only. It is not necessary to convert back again. The rest of the procedure for draining and filling the complete DRC system is described using the DRC Filling Device :VAS 6544 .
- Only approved oil may be used for filling or refilling. Refer to the Electronic Parts Information (ETKA).
- As a replacement part, shock absorbers and lines are delivered empty.
- Filling must only be performed at ambient temperature of approximately 20 °C.
- Lines/shock absorbers and central valves may only be evacuated and filled when they are installed and connected.
- While filling the DRC system, the gas reservoir to the pressure clamps is automatically checked for leaks at the piston in the central valve.
- Valves of filling device are open when ratchet levers are parallel to the flow direction.
- The valves must be kept closed during transport and storing the DRC Filling Device :VAS 6544 .
- Lines must not be bent.
Risk of eye injury.
- Wear protective eyewear!
Before filling the DRC system, make sure the oil reservoir for the DRC Charging Device :VAS 6544 and the connecting line between the pressure pump and oil reservoir are filled with fluid.
The used oil container on the DRC Filling Device :VAS 6544 must be empty and must be emptied after each charge.
Drain the old oil reservoir.
-- Remove the cap -arrow- from the used oil container -1- and drain the used oil.
-- Reattach the cap.
DRC Filling Device :VAS 6544 , Filling and Bleeding
-- Fill the oil reservoir -2- with new oil up to the marking and position the O-ring to the height of the oil level. Refer to the Electronic Parts Information (ETKA).
-- Close the shut-off valves -A- and -C- on the DRC Filling Device :VAS 6544 .
-- Close the needle valve -B-.
-- Connect the hose -2- to the used oil container -right arrow- and to the quick-release -4- on the DRC Filling Device :VAS 6544 .
-- Connect the Venturi injector -3- to the vent hose on the used oil container -left arrow- as shown.
-- Connect the compressed air to the Venturi injector -3-.
-- Open the locking valve -C-.
-- Open the locking valve -A- for approximately one to two seconds, until the connecting line -1- between the oil reservoir -2- and pressure pump is filled free of bubbles.
-- Close the locking valve -C-. Disconnect the compressed air connector from the Venturi injector.
Extracting/Evacuating
-- When the DRC is to be bled/evacuated, then select the "DRC, Filling (only RS models)" program. Refer to DIAGNOSTIC ENTRIES .
-- Start the selected program and follow the instructions on the Vehicle Diagnostic Tester display.
Risk of eye injury.
- Wear protective eyewear!
-- Turn the front wheel on the side to be evacuated outward.
The DRC system consists of two separate hydraulic systems. The central valves are connected diagonally to the applicable shock absorber.
-- Drain the DRC system as follows:
| Central Valve | Shock Absorber |
|---|---|
| 1 - left | Left front/right rear |
| 2 - right | Right front/left rear |
-- Remove the dust cap -arrow- from the front suction/fill valve.
-- Connect the fill line and quick-release fastener -1- from the Charging Device For DRC System :VAS 6544 . Charging Hose with Quick-Release Fastener to the front suction/fill valve on the wiring harness to be evacuated.
-- Remove the rear wheel on the side of the wiring harness to be evacuated. Refer to WHEELS AND TIRES .
-- Free up the wheel housing liner for the rear suction/fill valve.
-- Remove the dust cap -arrow- from the rear suction/fill valve.
-- Connect the filling hose and quick-release fastener -1- from the DRC Filling Device :VAS 6544 . Charging Hose with Quick-Release Fastener to the rear suction/fill valve on the wiring harness to be evacuated.
-- Connect the filling hoses . Charging Hose with Quick-Release Fastener to the connections -A- and -B- on the DRC Filling Device :VAS 6544 .
- The shut-off valves -A- and -C- on the DRC Filling Device :VAS 6544 are closed.
- Needle valve -B- closed.
- The hose -2- is connected to the used oil container -right arrow- and to the DRC Filling Device :VAS 6544 -4-.
- Venturi injector -3- connected to the used oil container vent hose -left arrow- on the DRC Filling Device :VAS 6544 .
- Compressed air connected to the Venturi injector -3-.
-- Open the valve -C- until the last of the oil is extracted from the DRC system. (Visible on the return hose -2- to the used oil container).
-- When the pressure manometer shows approximately negative 0.9 bar, close the valve -C- and disconnect the compressed air hose from the Venturi injectors.
-- Check for leaks.
- Vacuum must be stable for at least two minutes at negative 0.9 bar.
-- Check the oil level on the oil reservoir, fill with new oil up to the marking if necessary and position the O-ring to the height of the oil level. Refer to the Electronic Parts Information (ETKA).
Filling
The DRC system consists of two separate hydraulic systems. The central valves are connected diagonally to the applicable shock absorber.
-- Fill the DRC system as follows:
| Central Valve | Shock Absorber |
|---|---|
| 1 - left | Left front/right rear |
| 2 - right | Right front/left rear |
-- Open the needle valve -B- approximately two turns and let the oil run out of the oil reservoir on the DRC Filling Device :VAS 6544 into the evacuated DRC system.
Oil flows out of the oil reservoir in the connected DRC system. This is shown by the decreasing the oil level in the oil reservoir. Depending on the amount of oil remaining after extraction, the procedure may take several minutes. As the system fills up, the oil level goes down slower. If the level of the oil no longer moves, the first step of the filling process is complete.
-- Close the needle valve -B-.
-- Open the valve -A- and fill the DRC system to 22 bar by pumping the lever on the hand pump -1- several times.
While filling, make sure the oil reservoir on the DRC Filling Device :VAS 6544 does not run dry; fill the reservoir with new oil if necessary.
- When a pressure of 22 bar is reached, close the valve -A- and do not pump the hand pump lever any more.
Exceeding the maximum pressure of 22 bar does not improve the filling process. Caution! There is a risk of damaging DRC system components as well as the DRC Filling Device :VAS 6544 .
If the pressure does not reach 22 bar or if it continually drops, check all connections for damage or leaks. If no issues are found on the outside, the gas reservoir to the pressure clamps on the piston on the inside of the central valve is leaking. Replace the central valve.
-- Open the needle valve -B- slightly and let the pressure drop to 16 bar.
- Close the valve -B- when the indicator on the pressure manometer reaches the 16 bar marking.
The 16-bar graduation line on the scale is colored in green depending and the version and model of the pressure gauge. The marking has no meaning for this procedure and should be ignored.
The DRC system is filled.
-- Disconnect the filling hose with quick-release coupling on the DRC Filling Device :VAS 6544 . Charging Hose with Quick-Release Fastener from the rear and front suction/fill valve.
-- Mount the rear wheel. Refer to WHEELS AND TIRES .
-- Install the dust cap for the rear and front suction/fill valve.