Notes on separating hydraulic lines from Vario roof hydraulic unit - AH77.37-P-0001-01R
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MODEL 230.4 without CODE P99 (Special model "AMG Black Series")
Before loosening mounting plate connected to hydraulic lines No. 21, 22, 60, 100, 102 or 103 on valve block for roll bar Vario roof control hydraulic unit (RVC), relieve pressure in hydraulic line No. 100.
This can be accomplished by raising the roll bar hydraulically and then putting it down mechanically.
When the mounting plate is loosened on RVC [UVS] hydraulic unit valve block without previously relieving the pressure, the support ring on connection No. 100 on valve block is pressed out and the sealing ring below damaged. This causes irreparable damage to the RVC [UVS] hydraulic unit.