W211 E55 Electrical Issue
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E55 AMG
W211 E55 Electrical Issue
Something is draining the battery in my 2003 E55. The dome lights come on randomly as if the car doors are open, the alarm randomly goes off, and at night the headlights don't come on and the instrument cluster light stay off. I also had the instrument cluster repaired a couple of weeks ago, but i had this problem before the cluster went bad.
Is what causing this problem the gateway module, seat control module, or something else? I literally had my main battery replaced a couple of weeks ago, too. Any help is appreciated!
Is what causing this problem the gateway module, seat control module, or something else? I literally had my main battery replaced a couple of weeks ago, too. Any help is appreciated!
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From: dmv
2009 E550 2000 Honda civic mash n' go
Need to do a current draw test to isolate where current is coming from. Once you've isolated it you then can determine what exactly is causing draw. Voltmeter and amp clamp would be your best friends for this.
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From: Republic of Texas
'99 and '05 E55 AMG
I agree with Plutoe, put it on a proper diagnostic system and you will most likely have your answer within five minutes...
How much is your time worth? The longer you wait to have it properly diagnosed, the longer you will live with this problem.
The interior bus uses the front SAM, the rear SAM, and the passenger-side SAM. I would suspect (but only suspect) the front SAM. Especially if you own a 2003 without the rubber ECU/SAM cover, water infiltrates into the front SAM and ECU location. In model years 2004/2005, an additional rubber cover was installed over the plastic cover on the front SAM. Again, stop wasting time and put it on a diagnostic system.
Let us know what you find.
PS. adding the model year and, if possible, the build date of your car would help. The E55 had multiple wiring harnesses over the years so you must use the VIN to determine which harness applies to yours. Example: An E55 built on Tuesday, 31 May 2005, has a different wiring harness than an E55 built on Wednesday, 1 June 2005. Small differences, but important if you are trying to figure out the fuel system and it means they use a different control module.
How much is your time worth? The longer you wait to have it properly diagnosed, the longer you will live with this problem.
The interior bus uses the front SAM, the rear SAM, and the passenger-side SAM. I would suspect (but only suspect) the front SAM. Especially if you own a 2003 without the rubber ECU/SAM cover, water infiltrates into the front SAM and ECU location. In model years 2004/2005, an additional rubber cover was installed over the plastic cover on the front SAM. Again, stop wasting time and put it on a diagnostic system.
Let us know what you find.
PS. adding the model year and, if possible, the build date of your car would help. The E55 had multiple wiring harnesses over the years so you must use the VIN to determine which harness applies to yours. Example: An E55 built on Tuesday, 31 May 2005, has a different wiring harness than an E55 built on Wednesday, 1 June 2005. Small differences, but important if you are trying to figure out the fuel system and it means they use a different control module.
Last edited by bbirdwell; Mar 18, 2017 at 01:50 PM. Reason: clarification
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Joined: Apr 2015
Posts: 1,486
Likes: 46
From: dmv
2009 E550 2000 Honda civic mash n' go
DAS/Xentry will be little to no help in finding a draw on your battery system. You have to isolate the issue first before you do anything, DAS and Xentry arent going to isolate it for you...
