SL/R230: Soft Close Trunk Issue
Thread Starter
Junior Member
Joined: Nov 2019
Posts: 54
Likes: 28
From: Angola, Indiana
S65 AMG, SL55 AMG, SL500, SLK230, SLK350, GL320 CDI, CLK500
Soft Close Trunk Issue
Hello All,
I have read several post reference soft close trunk issues..... but, can't seems to find a thread that shows my particular issue.
I have a 2005 SL500. I have rebuilt the vacuum pump and done some testing and setting. The pump is making about 44psi pressure and 22Hg of vacuum... pulls 16.5 amps when running.
When the trunk is closed it drawls down and latches... but, the pump continues to run. I am not hearing any leaking from the latch.
The system keeps shutting down the trunk latch so the pump isn't burned up. Trying to figure out what tells the pump to shut off. Seems like it should be a switch in the latch mechanism.
I can buy a new latch.... just wanna be pretty sure that is the issue.
Any help is appreciated.
Thanks
Mark
I have read several post reference soft close trunk issues..... but, can't seems to find a thread that shows my particular issue.
I have a 2005 SL500. I have rebuilt the vacuum pump and done some testing and setting. The pump is making about 44psi pressure and 22Hg of vacuum... pulls 16.5 amps when running.
When the trunk is closed it drawls down and latches... but, the pump continues to run. I am not hearing any leaking from the latch.
The system keeps shutting down the trunk latch so the pump isn't burned up. Trying to figure out what tells the pump to shut off. Seems like it should be a switch in the latch mechanism.
I can buy a new latch.... just wanna be pretty sure that is the issue.
Any help is appreciated.
Thanks
Mark
MBWorld Fanatic!
Joined: Aug 2020
Posts: 1,339
Likes: 366
From: Gretna, NE
'03 SL55 Black, '03 SL500's Aegean, Mars Red, Tazanite, Alabaster, '11 S550 Flint Gray
If the pump is operating correctly for the other circuits once the trunk circuit is disabled, odds are very high that you have a leak in the trunk circuit. Since the latches have a 100% failure rate, I would suspect that first, but it could also be the line or pump connection. Latch fix is pretty quick and simple with JB Weld or something similar.
I have never had a PSE pump problem, but I think that the cycling of the pump is just an internal pressure switch. If it can't pull pressure because of a leak, it won't shut off (until the circuit is disabled).
I have never had a PSE pump problem, but I think that the cycling of the pump is just an internal pressure switch. If it can't pull pressure because of a leak, it won't shut off (until the circuit is disabled).
Thread Starter
Junior Member
Joined: Nov 2019
Posts: 54
Likes: 28
From: Angola, Indiana
S65 AMG, SL55 AMG, SL500, SLK230, SLK350, GL320 CDI, CLK500
Thanks for the input Mike.
The problem ended up being a leak in the pump housing. I had put a new impeller in the pump and also fabricated a test station to measure pressure and vacuum... as well as monitor the voltage and amp drawl. My test station also has the ability to install the 20amp fuse so that is tested also.
The problem was the silicone hoses inside the pump housing. I install a spring clamp on both ends of the pressure and vacuum hose. The leak was stopped and the system works perfectly.
One thing I would tell folks that rebuilding the pump is an easy process.... but, getting the pressure set correctly requires some effort. The Tork screws that hold the pump together are VERY sensitive. I built a test station for about $75. I was able to test the pump and set the pressure. Worked out great!!!
Thanks again for your input. I do appreciate the insight. I hope to be able to contribute to the forum..... not just be a “taker.”
Best Regards
Mark
The problem ended up being a leak in the pump housing. I had put a new impeller in the pump and also fabricated a test station to measure pressure and vacuum... as well as monitor the voltage and amp drawl. My test station also has the ability to install the 20amp fuse so that is tested also.
The problem was the silicone hoses inside the pump housing. I install a spring clamp on both ends of the pressure and vacuum hose. The leak was stopped and the system works perfectly.
One thing I would tell folks that rebuilding the pump is an easy process.... but, getting the pressure set correctly requires some effort. The Tork screws that hold the pump together are VERY sensitive. I built a test station for about $75. I was able to test the pump and set the pressure. Worked out great!!!
Thanks again for your input. I do appreciate the insight. I hope to be able to contribute to the forum..... not just be a “taker.”
Best Regards
Mark
