B Feelgood

I've recently acquired a 2003 SL55 with 30k on it. Upon receiving the car, I found a pinched vacuum line between the passenger seat (loud hissing noise after shutting car off) and a leaking vacuum box in the trunk lid (lid wasn't shutting all the way and was hissing). I fixed both of these items and they now work 100% correct now with zero leaks. I tried putting the top up/down when I got the car and it worked fine. It seemed to quit working after about a week of ownership or whenever I realized the two vacuum leaks.

The central locking system works, both seat lumbar/massage works, and soft close trunk works. Whenever I push the roll bar button or pull on the convertible top latch, I can hear a relay click behind my head in the trunk area but nothing happens (the windows still drop a 1/4" when pulling latch for convertible).

I hooked up Star and there are no codes present/stored. I checked the 20 amp fuse behind the passenger seat and it's good. I checked the flaps on the trunk lid and both are nice and tight. I tried disconnecting the auxiliary battery (newer battery that holds charge well) with no luck. I'm pretty much out of ideas and was hoping someone may have some additional insight before I'm forced into a stealership visit.

Heatwave

Feelgood: Please tell me a bit more about the pinched vacuum line near the passenger seat. All my vacuum systems seem to work OK, except the lumbar support controls ... both seats. I'm just asking where to begin looking for the failure point in the pneumatic line(s).

bobterry99

I would go back to Star Diagnosis and check the actual values for the roof controller to see if all of the prerequisites for roof operation are being met and to see if the roof control switch is being read.

sl55_maniac

First thing you want to confirm is if there is hydraulic fluid in the pump.

B Feelgood

I could literally hear an audible air hiss coming from the passenger side seat (underneath of where your right thigh would be) after shutting the car off. The lumbar/massage did not work in either seat. There is a grey/white vacuum line that comes up from underneath the carpet and is attached to the side of the seat. There is a rubber sleeve that covers the electrical wires and vacuum line in a bundle. My vacuum line somehow got pinched and was basically cut in half. I removed the passenger seat (5 bolts), cut the rubber sleeve, put a plastic vacuum splice in between the two broken lines, and put shrink wrap over it. In the picture below, I circled where mine was basically cut in half.

B Feelgood

Thanks for responding everyone. There is sufficient hydraulic fluid in the pump (in between min/max). I played around in Star checking values and then realized that maybe I checked the wrong fuse. The fuse I originally checked was for the 20 amp PSE pump. I went back and checked the 40 amp fuse for the hydraulic pump and sure enough it was broke. Heading to the parts store in a little bit to get a new fuse. Hopefully this is the quick fix I was hoping for, will update a little later.

B Feelgood

Bad news. I replaced the blown fuse for the hydraulic pump and it instantly blew the new one again. Any thoughts on possible causes? Is there anything else on this circuit (fuse 73) besides the hydraulic pump for the convertible top?

sl55_maniac

A blown fuse which was just replaced are symptoms of a bad motor on the pump. Your pump needs to be replaced or rebuilt.

B Feelgood

Thanks, that seems to be the culprit. A brand new pump carriers an MSRP of $2,000 and can be bought with discount for $1,400. Used pumps range from $500-$900. I found a company called Top Hydraulics, Inc. that rebuilds these pumps for $600 with a 3 year warranty. Has anyone used this company for a rebuild or have another one to suggest?

Also, does this pump use the same Pentosin CHF-11s hydraulic fluid that the suspension uses or something different?

latemodel21

Top Hydraulics is an Great company to work with. I sent them my pump last year and had it back and installed in a week. They also add improvements to the pump (improved seals?) as part of the service.

Not only do they turn the pump around in a couple of days, they send it back with the reservoir overfilled enough so that when you install it, your system will have the correct level after it auto-bleeds (ie, it comes with enough extra in it to refill that which you lose from the lines when you remove the pump).

I have seen nothing but great reviews for them.

Cheers,
Chris

B Feelgood

Chris,

Thanks for the input and your first hand experience dealing with the company is great to hear. Was your pump leaking or did it have an electrical short like mine is exhibiting? The little bit of feedback that I've found on the company via a Google search has also been very positive. I'm going to send away my pump on Monday for a rebuild instead of buying a new one.

Rudeney

I'll give another +1 for Top Hydraulics. Knock wood, I've not had any failures to need to use Klaus' services, but I have worked with several forum members who did. One of them even had several issues and Klaus went way beyond the call to help him get things resolved.

latemodel21

Like yours, my fuse was blown and a subsequent fuse blew instantly.

The removal and replacement is simple enough. Pay attention to the process of removing the lines that relates to lines holding pressure (roll bar lines?) as it can be a little messy and force the seal out in an awkward way.

cheers,
Chris

sl55_maniac

I would highly recommend Top Hydraulics as well. The rebuild with much better quality components replaced on the pump will be much better than a brand new pump purchased from MB and will also last longer.