SL/R230: Have Trunk Soft Close / Trunk Assist problems. Here is how to fix DIY.
#201
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My turn in the barrel with my '07 R230: trunk release on driver's door and trunk release button on key will not unlock the trunk. I can use the blade key contained in the battery-powered key fob to open the trunk manually ... insert the key in the trunk lock gizmo, give it a quarter turn, then manually depress the trunk-open gripper and the trunk lock releases and I can lift the trunk lid.
When I open the trunk, stand near it, and depress the trunk-open button on the key fob, I hear whooshing inside the lock mechanism. So ... I guess I have the failure others have cured with applications of Gorrilla Glue or other adhesives.
My car is a full 10-years old ... I'd rather replace the old lock/unlock gizmo than try gluing it.
My question:
What is the part number for the lock/unlock gizmo?
When I open the trunk, stand near it, and depress the trunk-open button on the key fob, I hear whooshing inside the lock mechanism. So ... I guess I have the failure others have cured with applications of Gorrilla Glue or other adhesives.
My car is a full 10-years old ... I'd rather replace the old lock/unlock gizmo than try gluing it.
My question:
What is the part number for the lock/unlock gizmo?
#203
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Startech: Many thanks for your prompt reply and the link. I greatly appreciate it.
#204
2006 SL600 not doing the soft close. When you close the trunk it clicks once but doesn't pull the trunk shut all the way unless you slam it. Resetting the PSE will make it work for about 30 seconds. I sealed all the little BB's with epoxy and no difference. I bought a new trunk latch from MB and same thing. What else can it be?
#205
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Audiopros1:
I wish I could help you. I ordered a replacement latch mechanism last week when my auto-latch mechanism quit auto-latching and quit releasing using the key fob button or the button on the driver's door ... figgered it was toast. Yesterday I stepped out to begin replacing the latch mechanism and ... Shazam! ... the sum***** was working again. And it was working as of just a few minutes ago ... both opens and closes like it's supposed to. So what caused the hiatus? I have no clue. I'll put the new latch mechanism on the shelf for future use. In the meantime ... if you figger out your problem, please post the solution here. Best of luck, Mate.
I wish I could help you. I ordered a replacement latch mechanism last week when my auto-latch mechanism quit auto-latching and quit releasing using the key fob button or the button on the driver's door ... figgered it was toast. Yesterday I stepped out to begin replacing the latch mechanism and ... Shazam! ... the sum***** was working again. And it was working as of just a few minutes ago ... both opens and closes like it's supposed to. So what caused the hiatus? I have no clue. I'll put the new latch mechanism on the shelf for future use. In the meantime ... if you figger out your problem, please post the solution here. Best of luck, Mate.
#206
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#207
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About the trunk soft-latch: now it's an intermittent problem on my R230.
My car doesn't have the auto-raise/auto-lower trunk lid feature ... just the remote release (switch on door and on key fob) and soft-latch mechanism. I posted earlier that the soft-latch unit had gone t/u and that I ordered a replacement rather than attempt the Gorilla Glue remedy. I have the new unit but haven't installed it because the OEM unit went back to working again ... except when it doesn't.
I hadn't opened or closed the trunk in two or three days. Last time I opened the trunk, I thumbed the button on the driver's door and ... surprise! ... the trunk latch released. I opened the trunk all the way, placed a few items inside, lowered the trunk to the initial latch point, then let the auto-latch mechanism complete the latching. Surprise again. Everything was working properly. I haven't operated the trunk release since then.
I drove to the gym this morning, grunted and sweated for a coupla hours, got in my car, drove home, parked in the garage, sat in the car while the garage door closed, then killed the engine. I neither opened nor closed the trunk. In that period of silence after the garage door closed and I killed the engine, I heard a faint mechanical clicking coming from the trunk ... like something was trying to do something, over and over. I thumbed the trunk release button on the door and the trunk mechanism cycled and released the trunk lid. I opened the trunk, then closed it to the soft-latch point and let the soft-latch unit do its thing. Silence after that.
After that long narrative, I ask this question: what's going on with my trunk release mechanism? There's no apparent air pump or air hose problem: the door latches and seat controls work without exception. The trunk latch either releases via the door switch or the key fob button ... or it doesn't, in which case I unlock it with the key that's part of the fob ... but it always performs the soft-latch process. Always.
Is this a problem SDS can detect and report? I'm a neophyte with SDS. Any suggestion(s) you may offer will be greatly appreciated.
My car doesn't have the auto-raise/auto-lower trunk lid feature ... just the remote release (switch on door and on key fob) and soft-latch mechanism. I posted earlier that the soft-latch unit had gone t/u and that I ordered a replacement rather than attempt the Gorilla Glue remedy. I have the new unit but haven't installed it because the OEM unit went back to working again ... except when it doesn't.
I hadn't opened or closed the trunk in two or three days. Last time I opened the trunk, I thumbed the button on the driver's door and ... surprise! ... the trunk latch released. I opened the trunk all the way, placed a few items inside, lowered the trunk to the initial latch point, then let the auto-latch mechanism complete the latching. Surprise again. Everything was working properly. I haven't operated the trunk release since then.
I drove to the gym this morning, grunted and sweated for a coupla hours, got in my car, drove home, parked in the garage, sat in the car while the garage door closed, then killed the engine. I neither opened nor closed the trunk. In that period of silence after the garage door closed and I killed the engine, I heard a faint mechanical clicking coming from the trunk ... like something was trying to do something, over and over. I thumbed the trunk release button on the door and the trunk mechanism cycled and released the trunk lid. I opened the trunk, then closed it to the soft-latch point and let the soft-latch unit do its thing. Silence after that.
After that long narrative, I ask this question: what's going on with my trunk release mechanism? There's no apparent air pump or air hose problem: the door latches and seat controls work without exception. The trunk latch either releases via the door switch or the key fob button ... or it doesn't, in which case I unlock it with the key that's part of the fob ... but it always performs the soft-latch process. Always.
Is this a problem SDS can detect and report? I'm a neophyte with SDS. Any suggestion(s) you may offer will be greatly appreciated.
#208
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2008 SL550, 2015 SLK250 (Wife's :))
I have read all the posts, as I am having the same issues with the closing assist with my 08 550SL. I did not think it had a soft latch system. I am going to start with disconnecting the battery 1st and go from there.
#209
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Emcinnis: I don't know anything about your car's history, but it's not uncommon for people to slam the trunk lid shut, rather than lowering it until the latch connects and then tightens the trunk lid securely. Your car's prior owner mighta been too rough with the trunk lid. If yours has been slammed too much, the soft-latch may be T/U ... I guess a new closing mechanism may be necessary. When you lower the trunk lid and let it make the initial coupling with the latch, does the lid just sit there? Can you hear sounds coming from the closing mechanism in the trunk lid ... like something is trying to work but can't complete its cycle?
#210
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2008 SL550, 2015 SLK250 (Wife's :))
I have the auto-raise/auto-lower trunk lid feature. Up until a month ago the lid would click a final time after it was closed. Now it closes shut but does not do the final click and the light on the instrument panel shows that trunk is open. Nothing happens if I push down on the lid as it is closing.
#211
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2008 SL550, 2015 SLK250 (Wife's :))
Well I just tried pushing hard on the trunk lid just as it completed the power assist cycle and it is now closed. I tried it again without pushing down on the lid and it again does not close completely. Looks like it is closed, but if I pull up on the lid you can feel a slight give. At least I can close the lid now by pushing hard right at the end of the power assist. Seems like maybe there is an adjustment that can be made, not sure.
#212
Member
Well I just tried pushing hard on the trunk lid just as it completed the power assist cycle and it is now closed. I tried it again without pushing down on the lid and it again does not close completely. Looks like it is closed, but if I pull up on the lid you can feel a slight give. At least I can close the lid now by pushing hard right at the end of the power assist. Seems like maybe there is an adjustment that can be made, not sure.
#213
Senior Member
The ball and socket clamp must be attached to the control rod as high up on the rod as you can get it after installation. I got a feeling your your a shade off.
#214
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I need the advice of Veterans of Trunk Latch Problems.
I put the top down this morning on my '07 SL550. Everything seemed to be in good order. Then I drove across town and purchased some pastries and attempted to put them in the trunk, but neither the trunk release button on my key fob nor the release button on the driver's door would open the trunk. So I pulled the little key out of the key fob and used it to unlock and open the trunk. Then I closed the trunk lid to the first click, expecting the soft-close mechanism to take over from there. But ... no joy. The soft-close did nothing.
So I drove home with the trunk latched only on the first click ... the trunk-open symbol appeared on the dash ... then I opened the trunk with the key fob key and removed our pastries. Tonight I checked the fuse blocks under the hood; no fuses were blown.
So ... where do I go from here? I have a new latch mechanism I've been putting off installing, but I'm not sure my problem is with the latch. Or is it? I do not hear the air pump that powers the latch operating ... so, do I have a pump problem?
What are the steps for troubleshooting this? I appreciate your attention and responses.
I put the top down this morning on my '07 SL550. Everything seemed to be in good order. Then I drove across town and purchased some pastries and attempted to put them in the trunk, but neither the trunk release button on my key fob nor the release button on the driver's door would open the trunk. So I pulled the little key out of the key fob and used it to unlock and open the trunk. Then I closed the trunk lid to the first click, expecting the soft-close mechanism to take over from there. But ... no joy. The soft-close did nothing.
So I drove home with the trunk latched only on the first click ... the trunk-open symbol appeared on the dash ... then I opened the trunk with the key fob key and removed our pastries. Tonight I checked the fuse blocks under the hood; no fuses were blown.
So ... where do I go from here? I have a new latch mechanism I've been putting off installing, but I'm not sure my problem is with the latch. Or is it? I do not hear the air pump that powers the latch operating ... so, do I have a pump problem?
What are the steps for troubleshooting this? I appreciate your attention and responses.
#216
Member
I would disconnect the trunk battery and reconnect. If the trunk pull down works once or twice, your pump is OK but timing out due to a leak. If nothing happens, then the problem is somewhere else. Do your power door locks work--if so, your pump is OK and you have a latch problem.
#217
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Cyglee and Next2pool:
Using a flashlight last night, I checked the fuses behind the passenger seat ... none appeared blown. I'll check again today in sunlight. Thanks for that suggestion.
I disconnected the negative post of the trunk battery, waited 30 seconds (or so), then reconnected: no change in anything.
Power locks do not work.
Thank you for your assistance.
Using a flashlight last night, I checked the fuses behind the passenger seat ... none appeared blown. I'll check again today in sunlight. Thanks for that suggestion.
I disconnected the negative post of the trunk battery, waited 30 seconds (or so), then reconnected: no change in anything.
Power locks do not work.
Thank you for your assistance.
#218
Senior Member
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Cancel this post.
Last edited by Heatwave; 09-14-2016 at 02:44 PM.
#219
Member
Heatwave-Pulling fuse 71 (3rd 20 amp fuse) in the compartment behind your passenger seat for 30 seconds will reset the trunk close assist portion of your PSE pump. The fuse will not be blown, but you have to wait 30 seconds for the circuit to reset. This circuit is designed to save your pump when it runs to long due to a possible leak. I bet that is what your code is about.
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Heatwave (09-14-2016)
#220
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Startech: I checked the fuses behind the driver's seat ... I do not see fuses behind the passenger's seat. I like your theory and will give it a try if I can find Fuse 71. It looks like there's a pretty substantial black frame gizmo beneath the storage panel on the passenger's side ... I can't see behind it or in the space to determine whether there are more fuses there. I hope not, but I'll check it more closely. This I know: I can't see anything in that space and I sure can't get my hand in there. Thank you for your advice ... I will pursue it.
Also ... I have a new trunk latching replacement device. I'm going to install it today. I'm thinking the latching mechanism might be t/u and isn't signaling the soft-close gizmo that the trunk lid has been lowered to its first latch position and is awaiting being pulled tight.
I'll post the results of my efforts. Again ... many thanks to all for the advice and suggestions. This is a great forum. But I wish it would quit "losing" my password.
Also ... I have a new trunk latching replacement device. I'm going to install it today. I'm thinking the latching mechanism might be t/u and isn't signaling the soft-close gizmo that the trunk lid has been lowered to its first latch position and is awaiting being pulled tight.
I'll post the results of my efforts. Again ... many thanks to all for the advice and suggestions. This is a great forum. But I wish it would quit "losing" my password.
#221
Member
The bottom of the compartment behind the passenger seat is actually a lid to the fuse panel. There are two releases towards the rear that you pull forward and pull up on the lid. It's tough and tight, dont give up.
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Heatwave (09-14-2016)
#222
Heatwave, "I checked the fuses behind the driver's seat ... I do not see fuses behind the passenger's seat." Is your car right side drive? The right side rear storage compartment underneath is where the fuses are hiding. The front panel (held by 2 spring clips) will pop off too, for more access/visibility.
Last edited by cyglee; 09-14-2016 at 04:33 PM.
#223
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Startech, Cyglee: Many thanks for your offers of assistance. I'm still stumped. Lemme recap this:
Yesterday I opened the top and it stowed in the trunk like it's supposed to.
Later in the day I tried opening the trunk with the key fob remote push button ... trunk wouldn't open. So I opened the trunk with the tiny key stowed in the remote. Trunk assist light was illuminated Red and would not lift the stowed roof.
Today I replaced the latch mechanism with a new unit I recently ordered. I closed the trunk lid hoping the soft-close latch would snug the trunk down like it's supposed to. No joy. Just like before.
I tried removing the stowage box unit atop the cubby hole behind the passenger's seat. That thing is held in with four Torx 30 screws. I got the screws out, but the molding that curves around the rear stowage area had the box stuck in place. I tried peeking into the fuse box behind the passenger's seat (my car is left hand drive ... standard USA).
Using a flashlight, I examined each fuse as best I could ... none appeared blown, but a closer inspection might disprove me.
Startech: you identified the fuse I should check as Fuse 71, the third 20-amp fuse. Is this third from the outboard side of the fuse box or third from the centerline side of the box? Color? I gotta go online and find a fuse diagram.
BTW ... door lock/unlock switches on dashboard don't work. While driving, the instrument panels are red and show the trunk open.
Maddening.
I really appreciate y'alls' good advice and assistance. If you have any more suggestions, please pass them on. Thanks, Mates.
Yesterday I opened the top and it stowed in the trunk like it's supposed to.
Later in the day I tried opening the trunk with the key fob remote push button ... trunk wouldn't open. So I opened the trunk with the tiny key stowed in the remote. Trunk assist light was illuminated Red and would not lift the stowed roof.
Today I replaced the latch mechanism with a new unit I recently ordered. I closed the trunk lid hoping the soft-close latch would snug the trunk down like it's supposed to. No joy. Just like before.
I tried removing the stowage box unit atop the cubby hole behind the passenger's seat. That thing is held in with four Torx 30 screws. I got the screws out, but the molding that curves around the rear stowage area had the box stuck in place. I tried peeking into the fuse box behind the passenger's seat (my car is left hand drive ... standard USA).
Using a flashlight, I examined each fuse as best I could ... none appeared blown, but a closer inspection might disprove me.
Startech: you identified the fuse I should check as Fuse 71, the third 20-amp fuse. Is this third from the outboard side of the fuse box or third from the centerline side of the box? Color? I gotta go online and find a fuse diagram.
BTW ... door lock/unlock switches on dashboard don't work. While driving, the instrument panels are red and show the trunk open.
Maddening.
I really appreciate y'alls' good advice and assistance. If you have any more suggestions, please pass them on. Thanks, Mates.
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Heatwave (09-14-2016)