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Reset/re-synchronizing procedure - battery replacement?

27K views 9 replies 5 participants last post by  Ruindr 
#1 ·
Cheers all!

I'm in need of disconnecting the battery, and while I've done this on my w201 and W202 numerous times, last time the battery was changed on R129 was at the dealership, and i read some odd things with electronics of this car... So indeed, I want to do it right...

Could someone please post a link or possible list a step by step procedures for re-synchronizing what ever is that I need to do after the battery is re-connected (throttle body/windows/top and whatever else and in what sequence)?

Its 1995 SL320... Hydraulics fully operational and the Hardtop is on the car at the moment (if it makes any difference)

Many thanks in advance!

Regards,
D
 
#2 ·
So far as I know, you re-synch the windows. And then reset your clock. That' all I ever did in my 96 SL320. The windows is done by holding the both switches down 5-10 seconds after they're all the way down. Then up for an extra 5- 10 seconds after they're up. I normally do it twice. It's to reset the auto-drop of the window when opening the door. But it is integrated into the soft-top computer. So if you don't so it, the top may not work.

The easiest way to know if it's done is the windows drop the right amount when opening. Mine go down 1/2 way when out of synch.
 
#5 ·
Thank you very you guys, appreciate it! It's when I did the "search", some horror stories allover the web and this site after battery change... I'm replacing steering wheel and running new wiring for aftermarket amplifier. So to re-cap:


  • Negative - off
  • Positive - off
  • Positive - reconnect
  • Negative - reconnect
  • Windows sync x2 - full up (5-10 sec) full down (5-10 sec)
  • If equipped with Steering Angle Sensor - full clock/clock turns with the car running

And there is NO need to re-sync the top and nothing to do with re-initializing the throttle body either?

Thanks again!

Regards,
D
 
#6 ·
Yup yup. Looks like a good order to me. There's no re-synch for the top other than the windows (just make sure it's all the way up or down or the hard top is locked in place). As I understand it the electronic throttle (the one where you can reset it and it adapts to your driving) was, for the SL320's, only in the 1997 model year.

A suggestion: Move your steering wheel all the way from the dashboard before disconnecting the battery. It'll make access easier.
 
#8 ·
Its important to know that the top won't go up and latch if the windows haven't been resynced. This caught me off guard after I replaced the battery and drove around for days with the top down, then took the car to work, and where I parked was NOT a neighborhood I would trust to leave the car open or unlocked. Fortunately, a quick search on this forum from my phone solved the problem.
 
#10 ·
Every time I reconnect the battery the windows positions themselves to half way open. I guess it's a default position stored in the controller, which indicates a power interuption and the need to re-sync. And a reminder to the user to do so.
 
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