Level Control Solenoid Valve: Testing and Inspection

Testing Pressure At Rear Axle Level Controller










DANGER:
- Risk of injury to skin or eyes from hydraulic fluid spraying out under pressure Risk of poisoning from swallowing hydraulic fluid
- Render the hydraulic system pressureless before commencing work on system Wear protective clothing and eye protection

1 Drain hydraulic system

CAUTION: General notes for working on vehicles with level control / ADS

2 Connect tester to level controller
3 Fill the reservoir with fluid (2)

CAUTION: Raise the fluid level to approximately 0.5 litres above the MAX graduation (a) on the dipstick (2a) for the test

DANGER:
- Risk of accident from vehicle starting off by itself when engine running Risk of injury from contusions and burns if you insert your hands into the engine when it is started or when it is running
- Secure vehicle to prevent it from moving off by itself
- Wear closed and close-fitting work clothes
- Do not touch hot or rotating parts

4 Start engine and allow to idle
5 Press suspension-control module lever to position "fill" (F)
6 Check the release pressure of the bypass valve in the hydraulic suspension-control module

CAUTION:
- Because the pressures are considerable, keep test as brief as possible
- Ensure that the reservoir contains sufficient fluid Never let the pump suck air

NOTE: The suspension-control module's bypass valve limits the supply pressure of the hydraulic pump. The bypass valve emits a whistling noise as it opens, Bypass valve release pressure

7 Set level controller lever to "Empty" position (L)
8 Switch off engine
9 Check base pressure of discharge valve in hydraulic suspension-control module Read base pressure on pressure gauge
- The system should reach base pressure after no more than a maximum of 3 minutes

NOTE: Leave tester connected

10 Allow the system to settle for approximately 5 minutes, then read the base pressure again
- The base pressure should not drop during this period with the system in its passive state
- If pressure falls, Replace the suspension-control module

DANGER:
- Risk of injury to skin or eyes from hydraulic fluid spraying out under pressure Risk of poisoning from swallowing hydraulic fluid
- Render the hydraulic system pressureless before commencing work on system
- Wear protective clothing and eye protection

11 Disconnect tester at level controller
12 Recharge hydraulic system