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CL500 2002 Windows not syncing

1570 Views 11 Replies 4 Participants Last post by  tim687
Hi, I am having a problem with my 2002 CL500 front windows as they will not sync/normalise. I have searched this and other forums, but cannot find the same issue I am having. I think I have tried everything suggested on all the forums I have found and am now out of ideas on what to do next. Any help/suggestions would be really appreciated.

I have tried all the versions of holding buttons up/down from online and my user manual and the windows refuse to sync. Also, if I open either front door, the window for that door drops all the way down and will not move with the window switches until I disconnect and reconnect the battery. Rear windows work fine with the switches and drop when the doors are opened, but will not go up automatically again. They will go back up with the window switches.

I bought the car with this problem and have so far tried the following:
  • Tried two other rear window modules
  • Tried replacement left and right door control modules
  • Replaced the drivers door window switches
  • Replaced one of the window motors and wiring
  • Went through the wires in both left and right door hinges and repaired a few broken wires
  • Found the interior light door switches were disconnected and reconnected them - interior light goes on/off ok
  • Scanned with Foxwell scanner and have no fault codes related to doors or windows
  • Checked live data with the Foxwell to confirm the window switches up/down is recognised/working
  • Foxwell in live data mode identifies both windows are not normalised (synced)
  • Tried with car running, not running and not running with battery charger attached to rule out this being a voltage issue
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Update. Still cannot get the Windows to normalize. Looking for a reasonably priced C3 multiplexer to use with the Xentry software I have installed on an old laptop. Since original post I have tried the following:
  • Replaced the other window motor and wiring
  • Replaced battery for a new one
  • Replaced right door lock (it was not working)
Yesterday I did a continuity check on all the wiring running through the door hinge except speaker and airbag wires as I know they are working. All the wiring had continuity into the door. I can now rule out wiring.
The interior light switches were both disconnected when I bought the car. If I connect the switches the dome light comes on and off when you open/close the doors as expected. If the ignition is on and I open a door, the window on that side drops all the way to the bottom and will not move again unless I disconnect and reconnect the battery.i have been fault finding assuming the problem was the windows were not synced.
Does anyone recognize a connection of interior light switches and windows dropping and have any suggestions where to look next? I have tried everything I can find on forums other than Xentry and I am looking for a C3 multiplexer cable just now. Any hints would be appreciated.
They should only come on when it is actually dark outside

I know that the rear windows are not automatic windows in the up direction, just wanting to make sure that we're not getting confused here

I think you'll really need Xentry for this, you'll have to read out the DCM states and actuate the power window motors
I was in my garage which might be dark enough for the interior dome light to go on. I will double check in the daylight if the dome light still comes on.
yes, I know rear Windows do not auto up. They are working fine going up and down manually and the auto down is functioning.
My problems are just with the front Windows.
I have ordered a C3 multiplexer today and it should be here in a few weeks, so looking forwards to seeing if Xentry finds any issues.
Thanks for your suggestions.
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Can anyone recommend a supplier for a C3 multiplexer?
I have not had any luck getting a C3 multiplexer So far. First order with ALicar S Store on Aliexpress timed out without them dispatching anything. Money was refunded. My second order with ALiKING Store on Aliexpress was delivered but did not work. Not even the power light comes on when plugged into car’s OBD. OBD works fine and I also tried plugging C3 into another car with no success. ALiKING have been difficult to deal with and spent about 7 hours over two days trying to change laptop settings before accepting C3 didn’t work. Not much progress so far agreeing return and refund.
Finally I have a working Xentry with C3 multiplexer. No fault codes related to DCMs. I have a fault code (B1019 Terminal KL.58D has -//- or short circuit) related to the overhead control panel which could be related as windows drop when door opens/dome light comes on). Investigation continues….
FIXED! Turns out my car had the EZS module changed by previous owner and it was set to vehicle type R230. I changed it to W215 with DAS and then I was able to normalize the windows and the auto drop/raise is back working on both front doors. Thanks for the earlier help and absolutely I would never have solved this without Xentry/DAS
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