SL/R230: R230 SL500 trunk not opening with manual key or any of the button, nor is my central
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Junior Member
Joined: Aug 2024
Posts: 27
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2003 Mercedes Benz SL500
R230 SL500 trunk not opening with manual key or any of the button, nor is my central
Hey everyone. About a few weeks ago I went to take the car out for a cruise on a nice sunny day after a couple of weeks of rain and the car sitting in my garage, I noticed that my doors were not unlocking with the remote so I thought the rear battery was dead or needed a charge. I used the manual key to access the boot, took the battery home and left it for a full charge until the next day. Then I went to re-install the battery and my boot wasn't opening with the key manually. So basically after trying for an hour straight to somehow make it work and get into the boot, I realized the only option was to break the 3rd brake light and find my access through that, which did work so I was able to put the acc battery back in. I started the car and then took it on a long drive to make sure nothing was out of line. I came back home after a couple of hours yet still my central locking system didn't work nor did my boot. I tried the button inside the car, the button on the key fob, the latch and not even the manual key. Now I am wondering what I am dealing with. could it be that the PSE pump has blown or it's not creating enough pressure? However, I should also mention that every time I operate any button that's got to do with the PSE pump I hear a click sound coming from the PSE pump in the boot, not sure if it's a good sign but worth mentioning.
Super Member
Joined: Sep 2021
Posts: 537
Likes: 115
From: Ann Arbor, MI
2004 SL600
Since 52 people have read your post with no responses yet, let me take a shot...
Very strange that your manual key does not work. I've had both batteries disconnected for weeks and after I "accidentally" close the trunk, the manual key works as it should. Unless something in the trunk latch changed from 2003 to 2004, I don't understand why the manual key wouldn't work. I would normally say the trunk latch has a mechanical fault, but you also say that sometimes the manual key works.
Not sure how it is related, buy keep in mind that with the rear/acc battery removed, the front battery can still power parts of the car.
Do you have a scanner to scan for codes?
Very strange that your manual key does not work. I've had both batteries disconnected for weeks and after I "accidentally" close the trunk, the manual key works as it should. Unless something in the trunk latch changed from 2003 to 2004, I don't understand why the manual key wouldn't work. I would normally say the trunk latch has a mechanical fault, but you also say that sometimes the manual key works.
Not sure how it is related, buy keep in mind that with the rear/acc battery removed, the front battery can still power parts of the car.
Do you have a scanner to scan for codes?
Thread Starter
Junior Member
Joined: Aug 2024
Posts: 27
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2003 Mercedes Benz SL500
well, I never had any problems with the manual key not opening the boot in the past and on different occasions when the battery was dead, I used the manual key to get into the trunk however since the last time I tried the manual key, it just doesn't work anymore. I'm thinking that I've also got an issue with the lock mechanism now as well as the central lock system, which could be due to the PSE pump failing or other things that might cause this problem. I removed fuse 71 to reset the pse pump but that didn't even solve the problem not even temporarily. I don't have a STAR myself but the indy shop that I took the car to a couple of times in the past for other works has one so I can ask him to do a scan for me.
Member
Joined: Feb 2003
Posts: 92
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From: Jupiter, FL
SL 550
One guy said he broke in through the "3rd" LED brake light - isn't the liner in the way there ?
Super Member
Joined: Sep 2018
Posts: 746
Likes: 184
From: Melbourne, Australia
2005 SL 500 R230
Ah I think you should be able to open the boot that way with the blade and lifting the latch - it should operate that way even if the battery is disconnected, so I think there may be somethings broken in the lock.
Can someone else help here if I have that wrong?
Can someone else help here if I have that wrong?
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Thread Starter
Junior Member
Joined: Aug 2024
Posts: 27
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2003 Mercedes Benz SL500
I could open the boot by breaking the 3rd brake light, which was my only way in after realizing that the manual key is not doing its job. I am still not sure what's causing the issue with the manual key not opening the boot all of a sudden, definitely should not have anything to do with any blown fuse or pse vacuum pump issues because as the name suggests its a manual key and should work to manually open the boot so the only thing I suspect here is that both my pse pump and the actual lock mechanism of my trunk need replacing/fixing.
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Thread Starter
Junior Member
Joined: Aug 2024
Posts: 27
Likes: 0
2003 Mercedes Benz SL500
JunoJim, im not sure what the issue is with yours but you can def open up the boot through the third brake light by breaking it then after fixing your issue just replace it with another of a used part-out SL or order a brand new one of ebay they shouldn't be that expensive.
Member
Joined: Feb 2003
Posts: 92
Likes: 0
From: Jupiter, FL
SL 550
3rd brake light
JunoJim, im not sure what the issue is with yours but you can def open up the boot through the third brake light by breaking it then after fixing your issue just replace it with another of a used part-out SL or order a brand new one of ebay they shouldn't be that expensive.
Oh boy, really stupid !!! My valet key would turn 90 degrees one way but only 45 the other way.
So, I finally used some WD-40 & a little more torque & it opened !!!
I guess now I'll have to take out that unlocking mechanism & glue it some more 😁
Last edited by JunoJim; Feb 27, 2025 at 07:32 PM.
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