The top on my 03 SL55 was working fine but my consumer battery was giving me issues with the open door->window drop. If the car sat for over 48hrs the windows would no longer drop during a door open event. I replaced the consumer battery and everything now works as it should except the top. The 30amp fuse (71) in the passenger rear glove box blows. If I replace it I can hear the hydraulic pump in the drivers side trunk running, it starts out as if no load then increasingly slows down sounding like its really working. If I pull the fuse it stops the pump but naturally when its reinstalled it will run until it blows.
I removed the pump (not the hoses) and inspected the lines and connections everything seems fine no indication of water issues. I tried disconnecting/reconnecting the consumer battery no joy. Ideas on what sensor is directing the pump to overrun its limits?
I removed the pump (not the hoses) and inspected the lines and connections everything seems fine no indication of water issues. I tried disconnecting/reconnecting the consumer battery no joy. Ideas on what sensor is directing the pump to overrun its limits?
Did some additional testing this morning and determined if I hold in the 30amp fuse then operate the roof it will fully retract but I must remove the fuse once its down or it will blow. It will also fully extend and close but once its done I must remove the fuse. In both cases you can hear the hyd pump running in the trunk until it blows the fuse.
Is there a pressure switch on the pump that detects when the pump action is complete and the pressure rises causing the switch to shut off the pump?
Is there a pressure switch on the pump that detects when the pump action is complete and the pressure rises causing the switch to shut off the pump?
I tested with a Foxwell (Mercedes database) and the car has no codes other than a phone code.
I was working alone and was certain it was the hydraulic pump that was running. As a double check I removed the relay, it was the PSE door & trunk pump under the hydraulic pump - never assume.
Knowing they are a point of failure I removed the trunk latch assembly, pressurized it to 4 psi and found two leaks. Epoxied them both, reinstalled and tested again. The system worked much faster but the pump would stop 25% of the time and continue running the rest causing me to remove the fuse. Pulled the PSE disassembled the case, cleaned all contacts (including the internal pressure switch) with contact cleaner then sprayed with WD40, reassembled and all of the PSE accessories work, doors, trunk, etc!
Knowing they are a point of failure I removed the trunk latch assembly, pressurized it to 4 psi and found two leaks. Epoxied them both, reinstalled and tested again. The system worked much faster but the pump would stop 25% of the time and continue running the rest causing me to remove the fuse. Pulled the PSE disassembled the case, cleaned all contacts (including the internal pressure switch) with contact cleaner then sprayed with WD40, reassembled and all of the PSE accessories work, doors, trunk, etc!
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