2005 S500 PSE Pump / Soft Close Door / Trunk Ticking
Thread Starter
Junior Member
Joined: Nov 2015
Posts: 42
Likes: 8
From: San Francisco Bay Area, California, USA
2005 S500 4Matic
2005 S500 PSE Pump / Soft Close Door / Trunk Ticking
My 2005 S500 4MATIC was having repeated ticking from the trunk's driver's side any time I'd sit in the car after driving.
I did a little research and read that it was probably the PSE pump in the trunk running, and confirmed that by putting my hand on it. (I already have the trunk carpet on the driver's side out for some previous work on the radio components in the trunk.)
Today I took the PSE pump out and disassembled the turbine stack to inspect it, and I was surprised to find that it all looked okay, No broken vanes or hub assembly. I carefully reassembled it, keeping everything in order and aligned (I'd marked it first) and tested the pressure. It put out over 45 PSI, (over 3 Bar) so the pressure is okay. I reinstalled, and just for good measure pulled the 20 amp yellow fuse under the back seat, then reinstalled it.
The PSE pump whirred to life and stopped, so I tested all four doors' soft-close function. On three of the doors, the pump ran for a second or two when I open the door, and again on soft close. But for the driver's door, it ran for about 12 seconds and then stopped. I tested this again around the car and got the same result.
So I know I have a working PSE pump, but it runs for about 12 seconds when I soft-close the driver's door. Does this indicate a leak at the driver's door soft-close module? Are there known issues with how-to repair guide info for dealing with these? I'm not sure what the pump running for 12 seconds on the driver's door soft-close is supposed to mean. Help me Obi-wan!
I did a little research and read that it was probably the PSE pump in the trunk running, and confirmed that by putting my hand on it. (I already have the trunk carpet on the driver's side out for some previous work on the radio components in the trunk.)
Today I took the PSE pump out and disassembled the turbine stack to inspect it, and I was surprised to find that it all looked okay, No broken vanes or hub assembly. I carefully reassembled it, keeping everything in order and aligned (I'd marked it first) and tested the pressure. It put out over 45 PSI, (over 3 Bar) so the pressure is okay. I reinstalled, and just for good measure pulled the 20 amp yellow fuse under the back seat, then reinstalled it.
The PSE pump whirred to life and stopped, so I tested all four doors' soft-close function. On three of the doors, the pump ran for a second or two when I open the door, and again on soft close. But for the driver's door, it ran for about 12 seconds and then stopped. I tested this again around the car and got the same result.
So I know I have a working PSE pump, but it runs for about 12 seconds when I soft-close the driver's door. Does this indicate a leak at the driver's door soft-close module? Are there known issues with how-to repair guide info for dealing with these? I'm not sure what the pump running for 12 seconds on the driver's door soft-close is supposed to mean. Help me Obi-wan!
MBWorld Fanatic!
Joined: Dec 2012
Posts: 2,474
Likes: 439
From: Ball Ground, GA (N of Atlanta)
2003 S500 2007 GL450
Most probably a leaking pneumatic actuator. You can expect the PSE system to shut down that function soon.
A search on this forum or on BenzWorld will give you dozens of helpful threads. A web search on W220 soft close will give you lots more info, including several YouTube videos. You will need to learn how to remove the "door card" (upholstery panel) and how to repair or replace the actuator.
A search on this forum or on BenzWorld will give you dozens of helpful threads. A web search on W220 soft close will give you lots more info, including several YouTube videos. You will need to learn how to remove the "door card" (upholstery panel) and how to repair or replace the actuator.
Thread Starter
Junior Member
Joined: Nov 2015
Posts: 42
Likes: 8
From: San Francisco Bay Area, California, USA
2005 S500 4Matic
Most probably a leaking pneumatic actuator. You can expect the PSE system to shut down that function soon.
A search on this forum or on BenzWorld will give you dozens of helpful threads. A web search on W220 soft close will give you lots more info, including several YouTube videos. You will need to learn how to remove the "door card" (upholstery panel) and how to repair or replace the actuator.
A search on this forum or on BenzWorld will give you dozens of helpful threads. A web search on W220 soft close will give you lots more info, including several YouTube videos. You will need to learn how to remove the "door card" (upholstery panel) and how to repair or replace the actuator.
