Trunk lock problem -need help
Thread Starter
Newbie
Joined: Apr 2021
Posts: 1
Likes: 0
w221
Trunk lock problem -need help
hello
W221, has anyone had a problem with the tailgate? The slide, after opening, shoots several times, when you close the hatch, it lowers it, but you can hear the characteristic shooting from the bolt.
Sometimes it does not lock the lock and the hatch opens automatically, I bought 3 locks and each works as the same, the problem occurred after replacing the battery. please help
W221, has anyone had a problem with the tailgate? The slide, after opening, shoots several times, when you close the hatch, it lowers it, but you can hear the characteristic shooting from the bolt.
Sometimes it does not lock the lock and the hatch opens automatically, I bought 3 locks and each works as the same, the problem occurred after replacing the battery. please help
MBWorld Fanatic!
Joined: Aug 2014
Posts: 5,286
Likes: 1,665
S500
the 221 doesn't have a tailgate, it has a boot lid
the closing can be the useful manual type or optional slow clunky and irritating self opening / closing (where you waste 3 mins of your life waiting to check it closed correctly).
then I believe there are ones with extra dead locking (mine makes noises like a few guys are locking fort knox when the boot closes (I guess those with the option of "heightened theft protection" ?)
the fault you mention does the car have auto open / close ?
broken wires to the boot lid is a standard Mercedes feature (usually seen with a blank screen when in reverse), but as so much can be going on with over engineered mechanisms used, I'd be more on a wiring fault or the closing switch muddled rather then the boot catch
the closing can be the useful manual type or optional slow clunky and irritating self opening / closing (where you waste 3 mins of your life waiting to check it closed correctly).
then I believe there are ones with extra dead locking (mine makes noises like a few guys are locking fort knox when the boot closes (I guess those with the option of "heightened theft protection" ?)
the fault you mention does the car have auto open / close ?
broken wires to the boot lid is a standard Mercedes feature (usually seen with a blank screen when in reverse), but as so much can be going on with over engineered mechanisms used, I'd be more on a wiring fault or the closing switch muddled rather then the boot catch
Junior Member
Joined: Dec 2020
Posts: 16
Likes: 6
From: Newport Beach, CA
2011 Range Rover SC Autobiography Black Edition
Hi Daniel Rybi,
You mentioned that this issue began following a battery replacement. With the information you have provided, I will assume that your W221 is between 2007 and 2009. Also, given that you said, "the hatch opens automatically," I take that you have the automatic open/close trunk lid option. Since you did not specify the model year of your W221, I can only speculate that maybe the battery you have replaced is the auxiliary battery located in the trunk.
With this in mind, it very well could be a wiring fault, as BOTUS has suggested. However, I believe that may be more common on vehicles with trunk lids with multiple pivoting and articulation points—like the SL-class. Two wiring harnesses run to the trunk lid, one on each arm. If I remember correctly, the left side wiring harness holds the backup camera wiring (if equipped) and the locking wire for the key lock. The right side wiring harness has the closing latch, two lights, interior latch release, and various other units integrated into the trunk lid above the license plate.
If you find that it is not a wiring fault, it could be as simple as having the automatic trunk lid normalized. Following replacement of the auxiliary battery may cause the trunk lid to become not normalized. Unfortunately, the remedy is only available through Mercedes DAS, as unplugging computer modules and fuses will not reset or re-normalize the trunk lid.
I hope this provides you with some solution options to investigate.
Best wishes,
Christopher
You mentioned that this issue began following a battery replacement. With the information you have provided, I will assume that your W221 is between 2007 and 2009. Also, given that you said, "the hatch opens automatically," I take that you have the automatic open/close trunk lid option. Since you did not specify the model year of your W221, I can only speculate that maybe the battery you have replaced is the auxiliary battery located in the trunk.
With this in mind, it very well could be a wiring fault, as BOTUS has suggested. However, I believe that may be more common on vehicles with trunk lids with multiple pivoting and articulation points—like the SL-class. Two wiring harnesses run to the trunk lid, one on each arm. If I remember correctly, the left side wiring harness holds the backup camera wiring (if equipped) and the locking wire for the key lock. The right side wiring harness has the closing latch, two lights, interior latch release, and various other units integrated into the trunk lid above the license plate.
If you find that it is not a wiring fault, it could be as simple as having the automatic trunk lid normalized. Following replacement of the auxiliary battery may cause the trunk lid to become not normalized. Unfortunately, the remedy is only available through Mercedes DAS, as unplugging computer modules and fuses will not reset or re-normalize the trunk lid.
I hope this provides you with some solution options to investigate.
Best wishes,
Christopher
