Okay You M-B Electrical Geniuses- A Good Question for You!
#1
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RE: Cause of M-B SL500 Control Module(s) short
SL500 was taken to a non-M-B brake repair. No elect. problems when it went in the shop.
When they were finished and returned car-- the control module for the Conv. Top/Hard top was bad and showed a fault a short, and a low beam control module was also shorted.
The shop acknowledged that the battery went dead (they stated was bad), and that they either tried jumping it, or ultimately removed it for charging.
A COINCIDENCE... or can damage be done to the electrical system by jumping the battery, or by shorting one of the wires?
Now the manager (for 27 of their stores) is investigating... and is asking all the local Mercedes experts if this can happen. The local dealership in Scottsdale has stated it cannot happen... that there are 3 different fuses protecting the system.... and that control modules go bad all the time!
My guy (factory trained) says that the electrical systems are very delicate and tempermental... and that any slight surge or variance or anomaly to the electrical can fry modules.
Maybe it was coincidental... but that possibility diminishes after their admission of electrical problems (battery being run down) as well as them jumping the battery and then pulling it out... which is more like a "smoking gun" admission.
SL500 was taken to a non-M-B brake repair. No elect. problems when it went in the shop.
When they were finished and returned car-- the control module for the Conv. Top/Hard top was bad and showed a fault a short, and a low beam control module was also shorted.
The shop acknowledged that the battery went dead (they stated was bad), and that they either tried jumping it, or ultimately removed it for charging.
A COINCIDENCE... or can damage be done to the electrical system by jumping the battery, or by shorting one of the wires?
Now the manager (for 27 of their stores) is investigating... and is asking all the local Mercedes experts if this can happen. The local dealership in Scottsdale has stated it cannot happen... that there are 3 different fuses protecting the system.... and that control modules go bad all the time!
My guy (factory trained) says that the electrical systems are very delicate and tempermental... and that any slight surge or variance or anomaly to the electrical can fry modules.
Maybe it was coincidental... but that possibility diminishes after their admission of electrical problems (battery being run down) as well as them jumping the battery and then pulling it out... which is more like a "smoking gun" admission.
#2
MBWorld Fanatic!
I was once showed a box by a Mercedes mechanic that he described as as R129 top control box destroyed by battery jumping. He said $5000.
#3
RE: Cause of M-B SL500 Control Module(s) short
SL500 was taken to a non-M-B brake repair. No elect. problems when it went in the shop.
When they were finished and returned car-- the control module for the Conv. Top/Hard top was bad and showed a fault a short, and a low beam control module was also shorted.
The shop acknowledged that the battery went dead (they stated was bad), and that they either tried jumping it, or ultimately removed it for charging.
A COINCIDENCE... or can damage be done to the electrical system by jumping the battery, or by shorting one of the wires?
Now the manager (for 27 of their stores) is investigating... and is asking all the local Mercedes experts if this can happen. The local dealership in Scottsdale has stated it cannot happen... that there are 3 different fuses protecting the system.... and that control modules go bad all the time!
My guy (factory trained) says that the electrical systems are very delicate and tempermental... and that any slight surge or variance or anomaly to the electrical can fry modules.
Maybe it was coincidental... but that possibility diminishes after their admission of electrical problems (battery being run down) as well as them jumping the battery and then pulling it out... which is more like a "smoking gun" admission.
SL500 was taken to a non-M-B brake repair. No elect. problems when it went in the shop.
When they were finished and returned car-- the control module for the Conv. Top/Hard top was bad and showed a fault a short, and a low beam control module was also shorted.
The shop acknowledged that the battery went dead (they stated was bad), and that they either tried jumping it, or ultimately removed it for charging.
A COINCIDENCE... or can damage be done to the electrical system by jumping the battery, or by shorting one of the wires?
Now the manager (for 27 of their stores) is investigating... and is asking all the local Mercedes experts if this can happen. The local dealership in Scottsdale has stated it cannot happen... that there are 3 different fuses protecting the system.... and that control modules go bad all the time!
My guy (factory trained) says that the electrical systems are very delicate and tempermental... and that any slight surge or variance or anomaly to the electrical can fry modules.
Maybe it was coincidental... but that possibility diminishes after their admission of electrical problems (battery being run down) as well as them jumping the battery and then pulling it out... which is more like a "smoking gun" admission.
maybe destroyed by *reversing* the polarity of the battery cables while jumping. That can and does destroy lots of modules.
#4
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Join Date: Aug 2004
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BMW E30. I've turned to the dark side.
i too have seen this happen. each time there was no real explanation. we 'assumed' that whoever jumped/charged the battery may have accidentally hooked up the cables backwards. either way they seemed to follow a dead battery. I'm assuming also you have a r129 car. what year?