Intermittent Window Issue
Thread Starter
Newbie
Joined: May 2016
Posts: 7
Likes: 0
From: Chicago
2000 CLK 430 Cabrio
Intermittent Window Issue
Hello,
Been lurking for a while, first post. I recently bought a '00 CLK 430 cabrio. Came with heaps of problems, been having a bunch of fun working them all out. This one is baffling me though. The windows stop working every...day or so? Sometimes I'll come out and they're fine, other times they aren't. Pretty annoying. If I disconnect the battery and reconnect, they're fine. It's just pretty annoying to get out, mess with the battery in the trunk, and then get back in, re-synchronize the auto windows. The top also doesn't work if the windows aren't working, presumably because it needs to roll the windows down first.
I'm assuming my motors are fine, because it happens to _every_ window at the exact same time. I'm also assuming that if it's a wiring issue that it's not in the doors, again due to every window failing at once. That's nice, I'm not too interested in taking apart the doors. Any ideas about what I could check? Could it have something to do with the ECU trying to remember where the windows are with the Hall effect sensor? That's the only thing I know that would be effected by disconnecting the battery.
I have a basic Bluetooth OBD2 code reader, it's not detecting anything (other than a P0450, something to do with the gas cap probably, unrelated) would a STAR Diagnostics machine be able to tell me anything? I could try to cozy up to a mechanic or dealership.
Any input would be welcome. I'm getting pretty close to just installing a kill switch and dealing with it.
Been lurking for a while, first post. I recently bought a '00 CLK 430 cabrio. Came with heaps of problems, been having a bunch of fun working them all out. This one is baffling me though. The windows stop working every...day or so? Sometimes I'll come out and they're fine, other times they aren't. Pretty annoying. If I disconnect the battery and reconnect, they're fine. It's just pretty annoying to get out, mess with the battery in the trunk, and then get back in, re-synchronize the auto windows. The top also doesn't work if the windows aren't working, presumably because it needs to roll the windows down first.
I'm assuming my motors are fine, because it happens to _every_ window at the exact same time. I'm also assuming that if it's a wiring issue that it's not in the doors, again due to every window failing at once. That's nice, I'm not too interested in taking apart the doors. Any ideas about what I could check? Could it have something to do with the ECU trying to remember where the windows are with the Hall effect sensor? That's the only thing I know that would be effected by disconnecting the battery.
I have a basic Bluetooth OBD2 code reader, it's not detecting anything (other than a P0450, something to do with the gas cap probably, unrelated) would a STAR Diagnostics machine be able to tell me anything? I could try to cozy up to a mechanic or dealership.
Any input would be welcome. I'm getting pretty close to just installing a kill switch and dealing with it.
MBWorld Fanatic!
Joined: Nov 2001
Posts: 1,258
Likes: 209
From: Boston North Shore
2001 CLK320 Cabrio
I've included a couple of thumbnails that explain how the N52 RB/Power Roof work.
Basically, the controller evaluates the inputs (e.g. shown on the left side as well as from the CANBus) and if correct, provides the necessary outputs (e.g. shown on the right side) to operate the RB and power roof system. Note that the window operation in our cabriolets is different that the coupe (e.g. front window operation via N69 door control modules and rear window by the N52/N72 lower control field modules
The RB/Power Roof is very complex and a suggestion would be to have the MB STAR software check for any stored diagnostic trouble codes, by a qualified technician. The cost should be around $100. Also ask for a print out of any stored codes and that they be cleared (some stored codes can keep the system from operating properly).
Having this information can greatly facilitate a solution.
PS:
Your OBDII scanner only reads fault codes related to emissions (not body trouble codes).
The reason your system works sometimes, other times not, is that when you disconnect the battery, you also temporarily clear the limit conditions, or the lack of, currently stored in the N69 controllers. When you reset the limits, they eventually get screwed up again. Note: The window direction and positions are determined by the Hall sensor located on each motor shaft.
Basically, the controller evaluates the inputs (e.g. shown on the left side as well as from the CANBus) and if correct, provides the necessary outputs (e.g. shown on the right side) to operate the RB and power roof system. Note that the window operation in our cabriolets is different that the coupe (e.g. front window operation via N69 door control modules and rear window by the N52/N72 lower control field modules
The RB/Power Roof is very complex and a suggestion would be to have the MB STAR software check for any stored diagnostic trouble codes, by a qualified technician. The cost should be around $100. Also ask for a print out of any stored codes and that they be cleared (some stored codes can keep the system from operating properly).
Having this information can greatly facilitate a solution.
PS:
Your OBDII scanner only reads fault codes related to emissions (not body trouble codes).
The reason your system works sometimes, other times not, is that when you disconnect the battery, you also temporarily clear the limit conditions, or the lack of, currently stored in the N69 controllers. When you reset the limits, they eventually get screwed up again. Note: The window direction and positions are determined by the Hall sensor located on each motor shaft.
