Dynamic Ride Control (DRC), System Draining And Filling: Extracting/Evacuating
Extracting, evacuating and filling the DRC line on vehicles with variable damping may be performed only when the damping setting is set to "COMFORT " mode.
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 evacuated toward the outside.
-- Remove the dust cap from the front evacuation/fill valve.
-- Connect the fill line and quick-release fastener -1- from the Charging Device For DRC System VAS6544 to the front evacuation/fill valve on the line to be evacuated. Refer to -item 3- "Fill Lines with Quick-Release Fastener" (See Figure).
-- Remove the rear wheel on the side of the line to be evacuated.
-- Free up the wheel housing liner for the rear evacuation/fill valve.
-- Remove the dust cap from the rear evacuation/fill valve.
-- Connect the fill line and quick-release fastener -1- from the Charging Device For DRC System VAS6544 to the rear evacuation/fill valve on the line to be evacuated. Refer to -item 3- "Fill Lines with Quick-Release Fastener".
-- Connect the fill lines to the connections -A- and -B- on the DRC Filling Device VAS6544. Refer to -item 3- "Fill Lines with Quick-Release Fastener" (See Figure).
The shut-off valve -A- and -C- on the DRC Filling Device VAS6544 closed.
Needle valve -B- closed.
The hose -2- is connected to the used oil container -arrow- and to the DRC Filling Device VAS6544 -4-.
Venturi injector -3- connected to the old oil reservoir vent hose -arrow- on the DRC Filling Device VAS6544.
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, 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.
Filling
Extracting, evacuating and filling the DRC line on vehicles with variable damping may be performed only when the damping setting is set to "COMFORT " mode.
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.
- The DRC line must be extracted and evacuated correctly in order to fill it correctly. Refer to EXTRACTING/EVACUATING .
-- Open the needle valve -B- approximately two turns and let the oil run out of the oil reservoir on the DRC Filling Device VAS6544 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 by pumping the lever on the hand pump -1- several times.
While filling, make sure the oil reservoir on the DRC Filling Device VAS6544 does not run dry; fill with 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 danger of damaging DRC system components as well as the DRC Filling Device VAS6544.
If a pressure of 22 bar cannot be reached or continually drops, then check all connections for damage and leakage. 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 20 bar.
- Close the valve -B- when the indicator on the pressure manometer reaches the 20 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.
DRC system is filled.
-- Disconnect the fill line and quick-release fastener on the DRC Filling Device VAS6544 from the rear and front evacuation/fill valve. Refer to -item 3- "Fill Lines with Quick-Release Fastener" (See Figure).
-- Mount the rear wheel.
-- Install the dust cap on the rear and front evacuation/fill valve.
-- End the Fill DRC >>function<< on vehicles with variable damping. Refer to Vehicle Diagnostic Tester.