SL/R230: 2003 SL55 PSE Pump...Fixed!!
Thread Starter
Junior Member
Joined: Apr 2011
Posts: 36
Likes: 5
sl55
2003 SL55 PSE Pump...Fixed!!
Symptoms:
Trunk only opened with key
Top won't open...says "Close Trunk Seperator"
20 AMP Fuse located behind passenger seat blown
When new fuse installed, pump runs, then slows down, then fuse blows again
Problem:
The PSE Pump is not being told to stop.
Solution:
1) PSE Pump is on left side of trunk under the roof pump.
2) Remove 4 nuts and rotate roof pump out of the way.
3) Remove sponge covering black box
4) Lift and move black box towards centre of the trunk as wires and yellow tubes will allow.
5) Disconnect the two wiring plugs near the back.
6) There is a small grey recessed clip holding each of the yellow/grey air lines in place. Use thumb/slot screwdriver to hold tab back while pulling to release each air line. Grey line may release pressure when removed.
7) LABEL each air line as removed!!!
8) Black box containing PSE pump can now be removed from car.
9) Use slot screwdriver/hand pressure to "split" open black box. Try to open it slowly as the actual PSE pump is fairly unsecured and will flop out.
10) Remove the 2 grey air line connection hubs by inserting slot screewdriver into the four slots to release tabs.
11) Remove 3 screws.
12) Circuit board now loose. There is a white 3/8" round plastic part attached to copper strip. Beside it is a second copper strip.
13) Look carefully and you will see this copper strip is actually 2 copper strips. Looks like they are there for some option my car doesn't have.
If they are touching each other the pump circuit is closed and the pump will not stop.I sleaved a plastic protector over 1 of these two copper strips to keep them apart.
Pump now operates normally.
If you know what to look and can work with needlenose pliers etc. the copper tabs are visible and can be inspected/repaired without removing the pump from the car and skipping steps 5-8 and 10-12.
Trunk only opened with key
Top won't open...says "Close Trunk Seperator"
20 AMP Fuse located behind passenger seat blown
When new fuse installed, pump runs, then slows down, then fuse blows again
Problem:
The PSE Pump is not being told to stop.
Solution:
1) PSE Pump is on left side of trunk under the roof pump.
2) Remove 4 nuts and rotate roof pump out of the way.
3) Remove sponge covering black box
4) Lift and move black box towards centre of the trunk as wires and yellow tubes will allow.
5) Disconnect the two wiring plugs near the back.
6) There is a small grey recessed clip holding each of the yellow/grey air lines in place. Use thumb/slot screwdriver to hold tab back while pulling to release each air line. Grey line may release pressure when removed.
7) LABEL each air line as removed!!!
8) Black box containing PSE pump can now be removed from car.
9) Use slot screwdriver/hand pressure to "split" open black box. Try to open it slowly as the actual PSE pump is fairly unsecured and will flop out.
10) Remove the 2 grey air line connection hubs by inserting slot screewdriver into the four slots to release tabs.
11) Remove 3 screws.
12) Circuit board now loose. There is a white 3/8" round plastic part attached to copper strip. Beside it is a second copper strip.
13) Look carefully and you will see this copper strip is actually 2 copper strips. Looks like they are there for some option my car doesn't have.
If they are touching each other the pump circuit is closed and the pump will not stop.I sleaved a plastic protector over 1 of these two copper strips to keep them apart.
Pump now operates normally.
If you know what to look and can work with needlenose pliers etc. the copper tabs are visible and can be inspected/repaired without removing the pump from the car and skipping steps 5-8 and 10-12.
Newbie
Joined: Jan 2010
Posts: 11
Likes: 0
Mercedes Sl500 2003
Nice Post!
I should have tried that too. I bought my pump brand new from this guy instead and now its working... Anyways, ill try to fix my old one and maybe sell it to whoever might need it here.
http://cgi.ebay.com/ebaymotors/ws/eB...#ht_500wt_1182
http://cgi.ebay.com/ebaymotors/ws/eB...#ht_500wt_1182
Newbie
Joined: Sep 2011
Posts: 1
Likes: 0
SL500
hello, i took apart the PSE pump and followed your directions is this what you are talking about? I see 2 prongs and one of them has this white plastic thing thats keeping one of the sets together I have a 2004 sl500
Thread Starter
Junior Member
Joined: Apr 2011
Posts: 36
Likes: 5
sl55
SL 55 PSE Pump
Great picture!
My problem was that the pump would not shut off. It would run till the fuse blew. The pump was not being told to shut down. If you have different symptoms, my solution may not work.
There are 2 sets of metal contacts as shown near the left in your picture, one that is in use by the white lifter (if I remember right when the pressure gets high enough the white lifter lifts, makes contact and turns off the pump and a "spare" set (for who knows what).
My spare set of contacts was making contact with each other, which continued to supply power to the pump. The "spare" set of contacts must NOT be making contact with each other. It was a while ago now but if I was guessing I'd think it's the lower set in your picture.
I separated the two metal contacts and sleaved one in plastic, which solved my problem.
There is also a set of 4 identical small doides on the board which are known to fail. Any electronics repair place could tell you if they are faulty.
Good luck!!
My problem was that the pump would not shut off. It would run till the fuse blew. The pump was not being told to shut down. If you have different symptoms, my solution may not work.
There are 2 sets of metal contacts as shown near the left in your picture, one that is in use by the white lifter (if I remember right when the pressure gets high enough the white lifter lifts, makes contact and turns off the pump and a "spare" set (for who knows what).
My spare set of contacts was making contact with each other, which continued to supply power to the pump. The "spare" set of contacts must NOT be making contact with each other. It was a while ago now but if I was guessing I'd think it's the lower set in your picture.
I separated the two metal contacts and sleaved one in plastic, which solved my problem.
There is also a set of 4 identical small doides on the board which are known to fail. Any electronics repair place could tell you if they are faulty.
Good luck!!
Senior Member
Joined: Oct 2006
Posts: 379
Likes: 3
From: Southcoast England
CL500 216
On this thing on these pumps the carbon type rotor built into the pump can shatter when the weather drops to 0c, the reason is that the hole in the rotor is too small, the rotor shrinks and splits rendering the whole pump faulty, it is always this when the pump blows the 20 amp fuse. there are no parts for these pumps.
I can always make up a good PSE pump from a water damaged one, and the broken rotor.
I can always make up a good PSE pump from a water damaged one, and the broken rotor.
Trending Topics
Thread Starter
Junior Member
Joined: Apr 2011
Posts: 36
Likes: 5
sl55
Different Problem
Television...it is not "always" a broken rotor. With a broken rotor I don't think the pump would run, the fuse would just blow immediately. My PSE pump ran for 5-10 seconds before blowing the fuse. The pump was not being told to stop pumping when it achieved the corrrect pressure.
Different problems.
Different problems.
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Newbie
Joined: Feb 2015
Posts: 1
Likes: 0
SL55 AMG 2004
Ebay seller has a replacement (rotor and 8 x blade) kit for SL55 PSE pump
On this thing on these pumps the carbon type rotor built into the pump can shatter when the weather drops to 0c, the reason is that the hole in the rotor is too small, the rotor shrinks and splits rendering the whole pump faulty, it is always this when the pump blows the 20 amp fuse. there are no parts for these pumps.
I can always make up a good PSE pump from a water damaged one, and the broken rotor.
I can always make up a good PSE pump from a water damaged one, and the broken rotor.
When my PSE pump failed due to a shattered rotor, I obtained a replacement graphite rotor and 8 x blades kit from ebay seller ... germanpartz1 ...
Newbie
Joined: Apr 2015
Posts: 1
Likes: 0
2003 SL 500
PSE Pump - reset requred after replacing??
I just replaced my PSE pump and things are still not working as they should be. The trunk will not do a soft close, the locks are still not working properly- the fuel door remains locked and the roof will still not open. It says on the screen to "visit workshop". I pulled all the fuses behind the passenger seat in the console to "reset" and still nothing.
Any other suggestions??
Any other suggestions??
Newbie
Joined: May 2015
Posts: 3
Likes: 0
sl350
sl350 pump
My PSE pump runs intermittently I have taken the "black box" out but not split it terminals look dry and free of corrosion. I can hear something "switching" when I press the door remote. any ideas please?
Newbie
Joined: Apr 2017
Posts: 1
Likes: 0
mercedes sl500
carbon rotor shattered , just one ring.
On this thing on these pumps the carbon type rotor built into the pump can shatter when the weather drops to 0c, the reason is that the hole in the rotor is too small, the rotor shrinks and splits rendering the whole pump faulty, it is always this when the pump blows the 20 amp fuse. there are no parts for these pumps.
I can always make up a good PSE pump from a water damaged one, and the broken rotor.
I can always make up a good PSE pump from a water damaged one, and the broken rotor.
thanks everyone
Junior Member
Joined: Nov 2019
Posts: 58
Likes: 11
From: ORLANDO, FLORIDA
2006 CLS55 & 2011 G55 & 2xE55 Wagon
Symptoms:
Trunk only opened with key
Top won't open...says "Close Trunk Seperator"
20 AMP Fuse located behind passenger seat blown
When new fuse installed, pump runs, then slows down, then fuse blows again
Problem:
The PSE Pump is not being told to stop.
Solution:
1) PSE Pump is on left side of trunk under the roof pump.
2) Remove 4 nuts and rotate roof pump out of the way.
3) Remove sponge covering black box
4) Lift and move black box towards centre of the trunk as wires and yellow tubes will allow.
5) Disconnect the two wiring plugs near the back.
6) There is a small grey recessed clip holding each of the yellow/grey air lines in place. Use thumb/slot screwdriver to hold tab back while pulling to release each air line. Grey line may release pressure when removed.
7) LABEL each air line as removed!!!
8) Black box containing PSE pump can now be removed from car.
9) Use slot screwdriver/hand pressure to "split" open black box. Try to open it slowly as the actual PSE pump is fairly unsecured and will flop out.
10) Remove the 2 grey air line connection hubs by inserting slot screewdriver into the four slots to release tabs.
11) Remove 3 screws.
12) Circuit board now loose. There is a white 3/8" round plastic part attached to copper strip. Beside it is a second copper strip.
13) Look carefully and you will see this copper strip is actually 2 copper strips. Looks like they are there for some option my car doesn't have.
If they are touching each other the pump circuit is closed and the pump will not stop.I sleaved a plastic protector over 1 of these two copper strips to keep them apart.
Pump now operates normally.
If you know what to look and can work with needlenose pliers etc. the copper tabs are visible and can be inspected/repaired without removing the pump from the car and skipping steps 5-8 and 10-12.
Trunk only opened with key
Top won't open...says "Close Trunk Seperator"
20 AMP Fuse located behind passenger seat blown
When new fuse installed, pump runs, then slows down, then fuse blows again
Problem:
The PSE Pump is not being told to stop.
Solution:
1) PSE Pump is on left side of trunk under the roof pump.
2) Remove 4 nuts and rotate roof pump out of the way.
3) Remove sponge covering black box
4) Lift and move black box towards centre of the trunk as wires and yellow tubes will allow.
5) Disconnect the two wiring plugs near the back.
6) There is a small grey recessed clip holding each of the yellow/grey air lines in place. Use thumb/slot screwdriver to hold tab back while pulling to release each air line. Grey line may release pressure when removed.
7) LABEL each air line as removed!!!
8) Black box containing PSE pump can now be removed from car.
9) Use slot screwdriver/hand pressure to "split" open black box. Try to open it slowly as the actual PSE pump is fairly unsecured and will flop out.
10) Remove the 2 grey air line connection hubs by inserting slot screewdriver into the four slots to release tabs.
11) Remove 3 screws.
12) Circuit board now loose. There is a white 3/8" round plastic part attached to copper strip. Beside it is a second copper strip.
13) Look carefully and you will see this copper strip is actually 2 copper strips. Looks like they are there for some option my car doesn't have.
If they are touching each other the pump circuit is closed and the pump will not stop.I sleaved a plastic protector over 1 of these two copper strips to keep them apart.
Pump now operates normally.
If you know what to look and can work with needlenose pliers etc. the copper tabs are visible and can be inspected/repaired without removing the pump from the car and skipping steps 5-8 and 10-12.
