Side mirror won't adjust after replacing door control unit
Thread Starter
Member
Joined: Mar 2013
Posts: 142
Likes: 3
From: UK
W221 S500 SWB
Side mirror won't adjust after replacing door control unit
Hi all,
Basically my front right (driver) side window stopped working a while ago, so I replaced the door control unit and it started working again. I guess it was a thermal fuse issue. Mirror folding and illumination etc are all working too.
Except the mirror adjustment, it does not work any more. The light on the switch doesn't even come on.
The weird thing is, I can actuate it fine in Xentry and move the mirror about all directions. I can also tell that in Xentry it can detect that I am pressing the right buttons, except the "Mirror lens adjustment" is never on.
So the motor is fine, the switches are fine, and the control unit knows about everything. But why doesn't it work? Any idea please?
This is a 2007 W221 S500 (S550) RHD.
Thanks.
Basically my front right (driver) side window stopped working a while ago, so I replaced the door control unit and it started working again. I guess it was a thermal fuse issue. Mirror folding and illumination etc are all working too.
Except the mirror adjustment, it does not work any more. The light on the switch doesn't even come on.
The weird thing is, I can actuate it fine in Xentry and move the mirror about all directions. I can also tell that in Xentry it can detect that I am pressing the right buttons, except the "Mirror lens adjustment" is never on.
So the motor is fine, the switches are fine, and the control unit knows about everything. But why doesn't it work? Any idea please?
This is a 2007 W221 S500 (S550) RHD.
Thanks.
Senior Member
Joined: Aug 2009
Posts: 427
Likes: 57
13 GL350, 14 SL550
Did you code the new module in Xentry (version code)?
It sounds to me like you need to version code it for the correct options on your car. Your new module doesn't seem to think you have power mirrors.
I believe it's under control unit adaptation or something like that. You can select regions, options, etc. There will be options for whether you have power seats, mirrors, etc.
I'm doing all of this from memory so may be a bit incorrect. But my point is check in Xentry to make sure it is coded properly.
It sounds to me like you need to version code it for the correct options on your car. Your new module doesn't seem to think you have power mirrors.
I believe it's under control unit adaptation or something like that. You can select regions, options, etc. There will be options for whether you have power seats, mirrors, etc.
I'm doing all of this from memory so may be a bit incorrect. But my point is check in Xentry to make sure it is coded properly.
Thread Starter
Member
Joined: Mar 2013
Posts: 142
Likes: 3
From: UK
W221 S500 SWB
Thanks for the reply.
No I have not done any coding in Xentry. When I select unit adaptation it tries to connect to online SCN.
So does that mean I gotta take it to a dealer?
By the way I think all W221 come with power mirrors.
No I have not done any coding in Xentry. When I select unit adaptation it tries to connect to online SCN.
So does that mean I gotta take it to a dealer?
By the way I think all W221 come with power mirrors.
Senior Member
Joined: Aug 2009
Posts: 427
Likes: 57
13 GL350, 14 SL550
You shouldn't have to SCN code it. That is the hard part and requires a dealer.
There should be some sort of other section in Xentry allowing you to select options. Initial Startup? Control Unit Adaptation? Can't remember exactly.
Yes in Europe and NA most do come with power mirrors, but remember Xentry allows you to select options for cars built worldwide. There were W221's with taxi meters, cloth seats, and manual mirrors depending on certain markets in the world. So yes, I would suspect power mirrors is a setting.
There is also an option to transfer coding from your old unit if you can't get this to work, and your old unit is still in OK enough condition (ie. not completely dead)
But look around.. I'm sure there is an option somewhere.
Worst case I need to replace one of mine in about a week or two when it arrives, so I can check then and let you know.
There should be some sort of other section in Xentry allowing you to select options. Initial Startup? Control Unit Adaptation? Can't remember exactly.
Yes in Europe and NA most do come with power mirrors, but remember Xentry allows you to select options for cars built worldwide. There were W221's with taxi meters, cloth seats, and manual mirrors depending on certain markets in the world. So yes, I would suspect power mirrors is a setting.
There is also an option to transfer coding from your old unit if you can't get this to work, and your old unit is still in OK enough condition (ie. not completely dead)
But look around.. I'm sure there is an option somewhere.
Worst case I need to replace one of mine in about a week or two when it arrives, so I can check then and let you know.
Thread Starter
Member
Joined: Mar 2013
Posts: 142
Likes: 3
From: UK
W221 S500 SWB
Just tried both initial unit start up and control unit adaptation, and both are asking me to do it online
https://imgur.com/a/dcY5Y
https://imgur.com/a/dcY5Y
Senior Member
Joined: Aug 2009
Posts: 427
Likes: 57
13 GL350, 14 SL550
Ok I did learn something a while ago that may be helpful.
i had a problem where the module was changed but still couldn’t actuate the left door mirror at all. Right worked fine and so did the button to switch between mirrors
Someone welded a spot on the car and didn’t disconnect the battery. After the welding the problem appeared
what I couldn’t figure out is after changing the module, why didn’t it start working again??
talked to a friend who is an experienced tech. He swore it was the button assembly. I said that they are just buttons but he disagreed. Apparently there are some smarts in the buttons (circuit board)
changed the button unit and everything worked!
So just a thought. It is possible that the issue is with the buttons and not the module. I actually put my old module back to confirm this and everything still works.
Try reinstalling your old module and buy a used good button unit if you have run out of ideas
i had a problem where the module was changed but still couldn’t actuate the left door mirror at all. Right worked fine and so did the button to switch between mirrors
Someone welded a spot on the car and didn’t disconnect the battery. After the welding the problem appeared
what I couldn’t figure out is after changing the module, why didn’t it start working again??
talked to a friend who is an experienced tech. He swore it was the button assembly. I said that they are just buttons but he disagreed. Apparently there are some smarts in the buttons (circuit board)
changed the button unit and everything worked!
So just a thought. It is possible that the issue is with the buttons and not the module. I actually put my old module back to confirm this and everything still works.
Try reinstalling your old module and buy a used good button unit if you have run out of ideas
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Newbie
Joined: Feb 2005
Posts: 2
Likes: 0
OK, forgot too mention. Have also change door switch and cable from door switch to door modul with new OEM. The only thing that not work is the knob to activate regulation of left/right mirror. If I test this from Xentry, adjustment of mirror works as expected. If I put in the old module, all functions works OK: The reason why I have change front door module is because I have retrofitted BSA
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W221 S600, W220 S55 AMG Kompressor, W124 300E, W140 S320, W210 E3204M W164 ML320 Bluetec
The have seen several early production W221s that will have an issue with the power windows becoming inoperable and a Software Upfate on the DCM remediated it.
I am almost very that the earliest production models had a bug in the software that made it into the production units, and the window actually would stop functioning on a particular date. The fix was to flash it with the current software with SDS. I am almost certain there was a DTB published on this topic.
I am almost very that the earliest production models had a bug in the software that made it into the production units, and the window actually would stop functioning on a particular date. The fix was to flash it with the current software with SDS. I am almost certain there was a DTB published on this topic.
