Flushing active body control (ABC) system

AR32.50-P-0026A

Flushing active body control (ABC) system

2.2.07

 

Remove/install

 Danger!

Risk of injury to skin or eyes caused by hydraulic fluid spraying out under high pressure. Risk of poisoning caused by swallowing hydraulic fluid.

Depressurize the hydraulic system completely before starting any work on the system. Wear protective clothing and safety glasses.

AS00.00-Z-0013-01A



It is essential to ensure the utmost cleanliness throughout the entire procedure as even the smallest dirt particles in the hydraulic components can lead to malfunctions and a total failure of the ABC system



Always observe the work procedure; failure to do so will cause damage and thus result in total failure of the ABC system



When the work has been completed, cooling of the hydraulic fluid (after the engine is switched off) will cause the body to be lowered

1

Pull dipstick out of ABC expansion reservoir and check color of hydraulic fluid

 If the hydraulic fluid (ATF) is red, the red hydraulic fluid (ATF) must be replaced with green hydraulic fluid (Pentosin) and the ABC system must be flushed out completely.

2

Check and correct oil level in ABC expansion reservoir

 Use the measurement opening to correct the oil level.



Hydraulic fluids (Specification 345.0)

BB00.40-P-0345-00A

3

Connect STAR DIAGNOSIS, perform quick test routine and erase fault memory if necessary

4

Start engine and run at idling speed

 Wheels in straight-ahead position.

5

In Suspension menu of STAR DIAGNOSIS, select "Actuate all suspension struts alternately in circular sequence (rodeo)" and start program

 The hydraulic fluid is heated to approx. 80 °C.

 The program takes approx. 15 min.

6

Turn off engine

7

Detach return line from ABC expansion reservoir and guide into a suitable receptacle

 The receptacle must have a capacity of at least 15 l.

8

Detach cover from ABC expansion reservoir, remove filter element and reseal ABC expansion reservoir

See Filter ABC hydraulic fluid.

AR32.50-P-0025A

9

Start engine and run at idling speed

10

Start flushing procedure; to do so, select "Actuations/Actuate front and rear suspension struts alternately (pitching)" in Suspension menu of STAR DIAGNOSIS and start program

 The vehicle is raised and lowered alternately at the front and rear axle and hydraulic fluid is discharged from the return line.

11

Monitor hydraulic fluid level in ABC expansion reservoir through measurement opening

 As soon as the ABC expansion reservoir is 3/4 empty, pour in hydraulic fluid continuously through the measurement opening until the ABC system has been flushed out with approx. 10 l of fresh hydraulic fluid.

When pouring in the hydraulic fluid, do not use the normal ABC funnel with filter as this funnel does not allow the required quantity of hydraulic oil to pass through.

Make sure that the funnel used is absolutely clean (do not bring the funnel into contact with linty rags; wrap the funnel in clean protective foil after use).

 Never allow the tandem pump to run dry.

If there is a danger of the tandem pump running dry, switch off the engine, pour in hydraulic fluid and go back to operation step 9.



Hydraulic fluids (Specification 345.0)

BB00.40-P-0345-00A

12

Turn off engine

13

Replace and install filter element

See Filter ABC hydraulic fluid.

AR32.50-P-0025A

 Replace the old 10 µm filter element with a new 3 µm filter element.

14

Seal ABC expansion reservoir

15

Attach return line at bottom of ABC expansion reservoir

16

Check and correct oil level in ABC expansion reservoir

 Use the measurement opening to correct the oil level.



Hydraulic fluids (Specification 345.0)

BB00.40-P-0345-00A

17

Perform engine test run and check that ABC system is functioning correctly and is not leaking

 STAR DIAGNOSIS must be connected.

18

Disconnect STAR DIAGNOSIS from vehicle