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 modified or updated to match DRC Filling Device VAS 6544. The following choices are possible:
Special Tools And Workshop Equipment Required
- DRC Filling Device VAS 6209/4
- The DRC Filling Device VAS 6209/4 serves as an upgrade to the DRC Charging Device VAS 6209 already found in dealerships.
- Retrofit Kit, DRC System VAS 6209/5
- The Retrofit Kit, 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 Filling Device for DRC System VAS 6544. The DRC System Supplementary Kit VAS 6209/6 is also necessary.
- DRC System Supplementary Kit VAS 6209/6
- The Supplement Kit, DRC System VAS 6209/6 is needed to upgrade the DRC Charging Device, Pressure Pump VAS 6209/3 to the Filling Device for DRC System 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.
- DRC Filling Device VAS 6544
Updating the equipment for the DRC system must be done one time only. It is not necessary to convert back again. The procedure for draining and filling the complete DRC system is described using the DRC Filling Device VAS 6544.
Only approved oil for filling and draining must be used .
As a replacement part, shock absorbers and lines are delivered empty.
Filling must only be performed at ambient temperature of approximately 20 °C (68 °F).
Lines/shock absorbers and central valves may only be sectioned, evacuated and filled when they are installed and connected.
- Extracting, evacuating and filling the DRC line on vehicles with the variable damping may be performed only when the damping setting is set to "COMFORT".
- To extract, evacuate and fill the DRC line, start the Fill DRC >>function<< on the Vehicle Diagnostic Tester under address word 14 in "Guided Functions".
- If the mode is activated, the system goes into "COMFORT" mode and can no longer be changed manually. The yellow indicator lamp in the instrument cluster turns on when filling mode is active.
While filling the DRC system, the gas reservoir to the pressure clamps is automatically checked for leaks at the piston in the central valve.
Always wear safety goggles!
Valves of filling device are open when ratchet levers are parallel to direction of flow.
The valves must be kept closed during transport and storing the DRC Filling Device VAS 6544.
Lines must not be bent.
Required Equipment
- Not required
- Not required
- Fill lines with Quick-Release Fastener
- Venturi Injector with Exhaust Hose
- From the DRC Charging Device VAS 6209
- Connecting Hose
- From the DRC Charging Device VAS 6209
- DRC Filling Device VAS 6544
- Container for Used Oil
- Empty before starting the work
- Identification: red dot
Before filling the DRC system, make sure the oil reservoir for the DRC Charging Device VAS 6544 and the line between the pressure pump and oil reservoir are filled with oil.
The used oil container on the DRC Filling Device VAS 6544 must be empty and must be emptied after each charge.
Drain Old Oil Reservoir
-- Remove the cap -arrow- from the old oil reservoir -1- and drain the old oil.
-- Install the cap -arrow- on the old oil reservoir -1-.
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 .
-- Close the shut-off valve -A and C- on the DRC Filling Device VAS 6544.
-- Close the needle valve -B-.
-- Connect the hose -2- to the old oil reservoir -arrow- and to the quick-release fastener -4- on the DRC Filling Device VAS 6544.
-- Connect the Venturi injector -3- and vent hose to the old oil reservoir -arrow- as illustrated.
-- Connect the compressed air to the Venturi injector -3-.
-- Open the locking valve -C-.
-- Open the locking valve -A- briefly, for approximately one to two seconds, until the connecting line -1- between the oil reservoir -2- and pressure pump is filled and does not contain bubbles.
-- Close the locking valve -C-. Remove the compressed air connector form the Venturi injector.
Extracting/Evacuating
- Extracting, evacuating and filling the DRC line on vehicles with the variable damping may be performed only when the damping setting is set to "COMFORT".
- To extract, evacuate and fill the DRC line, start the Fill DRC >>function<< on the => Vehicle Diagnostic Tester under address word 14 in "Guided Functions".
- If the mode is activated, the system goes into "COMFORT" mode and can no longer be changed manually. The yellow indicator lamp in the instrument cluster turns on when filling mode is active.
Always wear safety goggles!
-- In vehicles with variable damping, start the Fill DRC >>function<< on the Vehicle Diagnostic Tester under address word 14 in "Guided Functions".
-- Turn the front wheel on the side to be sectioned toward the outside.
-- Remove the dust cap from the front suction/fill valve.
-- Connect the fill line and quick-release fastener -1- from the Charging Device For DRC System VAS 6544 -item 3- 3 to the front suction/fill valve on the line to be sectioned.
-- Remove the rear wheel on the side of the line to be sectioned.
-- Free up the wheel housing liner for the rear suction/fill valve.
-- Remove the dust cap from the rear suction/fill valve.
-- Connect the fill line and quick-release fastener -1- from the Charging Device For DRC System VAS 6544 -item 3- 3 to the rear suction/fill valve on the line to be sectioned.
-- Connect the fill lines 3 to the connections -A and B- on the DRC Filling Device VAS 6544.
The shut-off valve -A and C- on the DRC Filling Device VAS 6544 closed.
Needle valve -B- closed.
The hose -2- is connected to the used oil container -arrow- and to the DRC Filling Device VAS 6544 -4-.
Venturi injector -3- connected to the old oil reservoir vent hose -arrow- on the DRC Filling Device VAS 6544.
Compressed air to the Venturi injector -3- connected.
-- 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 reservoir).
-- When the pressure manometer shows approximately negative 0.9 bar (13 psi), 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 (13 psi).
-- 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.
Extracting, evacuating and filling the DRC on vehicles with the 3-stage damping may be performed only when the damping setting is set to "COMFORT".
Filling
- Extracting, evacuating and filling the DRC line on vehicles with the variable damping may be performed only when the damping setting is set to "COMFORT".
- To extract, evacuate and fill the DRC line, start the Fill DRC >>function<< on the Vehicle Diagnostic Tester under address word 14 in "Guided Functions".
- If the mode is activated, the system goes into "COMFORT" mode and can no longer be changed manually. The yellow indicator lamp in the instrument cluster turns on when filling mode is active.
-- 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 from the reservoir into the connected DRC system. This is shown by the decreasing 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 (319 psi) 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 with reservoir with new oil if necessary.
- When a pressure of 22 bar (319 psi) is reached, close the valve -A- and do not pump the hand pump lever any more.
Exceeding the maximum pressure of 22 bar (319 psi) 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 (319 psi) 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 (232 psi).
- Close the valve -B- when the indicator on the pressure manometer reaches the 16 bar (232 psi) marking.
The 16 bar (232 psi) 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.
DRC system is filled.
-- Disconnect the fill line and quick-release fastener on the DRC Filling Device VAS 6544 3 from the rear and front suction/fill valve.
-- Mount the rear wheel.
-- Install the dust cap on the rear and front suction/fill valve.
-- End the Fill DRC >>function<< on the Vehicle Diagnostic Tester on vehicles with variable damping.