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Hi
My car has slow load assist(up) and very slow roll bar(up) operation.
- I tried to find leakage at all cylinders but couldn't see leaked oil.
- hydraulic fluid is correct level
- DAS doesn't show any error
Please help suggest how to diagnose or correct this problem. Any procedure I should try? Thank u.
Mercedes issued a service bulletin to its dealers on resolving noisy, slow hydraulics operation. According to that bulletin, a possible cause is: "An air bubble is present above the upper intake hole in the expansion reservoir of the hydraulic unit" (picture).
The solution is to unbolt the pump assembly, separate the electrical connector, prop up the assembly with the motor end raised, reconnect the electrical connector, and then operate the roof several times.
That procedure has never benefited me, but being so quick and easy to do, it seems like a worthwhile starting point.
.
Now new problem occurs while slow roll bar and slow loadassist still exist. Trunk lid won't move from upright position when open the roof or close the roof. For open roof operation, it went smooth until the step that trunk lid supposes to move from upright poaition, but it wouldn't. I needed to help push extra inch or 2, then lid closed and locked. As for close roof operation, it was smooth until the trunk lid wouldn't close itself, and I needed to help push 1 or 2inches from up right position, then the lid closed and locked.
Has anyone experience the same? All cylinders checked and no leak. While cylinder 8is also fast when moving trunk lid from close position to upright position.
Mercedes issued a service bulletin to its dealers on resolving noisy, slow hydraulics operation. According to that bulletin, a possible cause is: "An air bubble is present above the upper intake hole in the expansion reservoir of the hydraulic unit" (picture).
The solution is to unbolt the pump assembly, separate the electrical connector, prop up the assembly with the motor end raised, reconnect the electrical connector, and then operate the roof several times.
That procedure has never benefited me, but being so quick and easy to do, it seems like a worthwhile starting point.
.
Thanks for the tip. I tried and it didn't work for me. Now trunk lid cannot move from upright position to close position without a little finger push, from close position to upright position, it worked fast.
Now trunk lid cannot move from upright position to close position without a little finger push, from close position to upright position, it worked fast.
I experienced this identical symptom on a car I was repairing a couple of years ago. The roll bar was painfully slow to move. As I recall I repeatedly raised/lowered the roll bar, and after perhaps twenty minutes it got faster to the point where it moved at normal speed. Then I operated the roof, and the trunk lid operation was restored. The only explanation that I can think of is that air worked its way through the hydraulic system.
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