Can't Open Trunk - '05 CL500
I am unable to open my trunk.
I usually open it with the hand switch above the license plate, but that (suddenly) stopped working.
The key FOB will also open the trunk (when I choose to use it), but now (suddenly) it won't open it either. It still opens the doors, so not a fob issue.
The switch on the driver door has also worked in the past, but (suddenly) it doesn't work either.
I pulled the actual key from the key fob and tried it in the keyhole above the license plate as well....
It enters the hole fine (no blockage) and turns in all directions without resistance...but does not open the trunk.
There doesn't appear to be any obvious entrance to the trunk from the back seat area. There is a console there, but nothing that appears to allow entrance into the trunk area.
I think I read somewhere that it is possible to access the locking mechanism after removing the license plate and the body trim under that, but not sure.
I have a trip to make this weekend and what really concerns me is having a flat and not able to access the jack/tire.
Before I bring it to the dealer, I would like to attempt opening it myself. I would appreciate your assistance. I am not a mechanic but not afraid to explore. If you could point me in the right direction I would certainly appreciate it.
Rock
It is almost certainly a bad wire in the bundle that feeds the trunk, which pulls out and stretches when trunk is opened. Bundle is at right rear near the hinge. One way is to open the bundle (take off the retractor mechanism) and look for bad wires. Another way is to check each wire with a multimeter where it terminates at each place on the trunk accessories (have to take off the trunk trim to expose all the gadgets, which is not hard). If it's supposed to be hot (12v) it should be, grounds same. You can check by running temporary feeds and grounds from the taillight harness by using alligator clips. Find one that shows no current, use a temporary feed, and verify if that's the cause. At that point you can run a new wire or repair the broken one in the harness. This cause and fixes also work with "No 3rd Brake light" and other codes and issues in the trunk.
The other possible reason for your issue is a loss of vacuum to the trunk release. The trunk release is a combination of electrical and vacuum-actuated devices - typical German Over-Engineering :-). Search for posts on how to re-epoxy the release valves and for checking vacuum lines. If you had the problem come up all of a sudden, however, I would vote for cause #1 above.
Last edited by smartadze; May 17, 2016 at 01:55 PM.
For the record, I did try the key again but got the same results.
Thanks for all of the info SMARTADZE - I will surely make use of your attachments once I get into the trunk. I will be checking the fuses first!
I couldn't agree more about the Over-Engineering. I recently had to spend the $4500 to get my power-steering back. To this day I still get funny looks when I tell people my suspension is tied to my power steering! Jeez! So, does the dealer use the "drill hole" method or do they have a "secret entrance"
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I finally got the trunk open using the metal key.
I now understand why everyone kept pointing me there. However, when I was attempting to open with the metal key previously, it would simply turn...in either direction without any thing happening. And yes, I was pushing in on the "button" at various points while turning the key.
At wit's end, I had my daughter sit on the trunk lid. As she was sitting there, I turned the key and FINALLY felt something catch when I pushed in the button! Once that happened, it was just a matter of getting her to stand up at the right moment I turned the key and it opened. WHEW!
So, having done that, I attempted to do it solo.
Sure enough, by applying pressure downward on the trunk lid, directly above the locking mechanism (with forearm/shoulder), turning the key, and pushing the button all at the same time (sounds harder than it is), I was able to open the trunk at will.
So, with that out of the way, I can focus on fixing the original problem!
Thanks to everyone for helping with that issue.






