Does the battery control module need coding?
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2006 E55 AMG
Does the battery control module need coding?
I have a 2006 E55 with the red battery light on. I scanned with xentry and have no communication to the battery control module. Merc no longer has these in stock so I ordered a used one from fleabay. Do I need to virginize/code the replacement?
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From: Republic of Texas
'99 and '05 E55 AMG
Circuit 30 is constant power. You are disconnecting the BCM from its constant power supply; sort of like a "hard" reboot on a computer.
Circuit 15 is switched power; there are several subcircuits (e.g. circuit 15R) that activate in sequence as the system comes online.
Circuit 15 is switched power; there are several subcircuits (e.g. circuit 15R) that activate in sequence as the system comes online.
MBWorld Fanatic!
Joined: Jan 2014
Posts: 3,966
Likes: 1,315
From: Republic of Texas
'99 and '05 E55 AMG
Errata; Circuit 30 is unfused; direct connection between battery and module (alternator). Circuit 30U is fused; direct connection to the battery but with a fuse inline (starter motor on some models). The latter is primarily the diesel versions of the W211 which use a 250 amp fuse in the harness. The schematics for the W211 E55 (U137 - applicable to the M112 and M113 engines) do not show a fuse inline. So...multiple versions of the schematics depending upon version and always fun (not!) to work through trying to understand the circuitry.
Last edited by bbirdwell; Mar 25, 2026 at 10:01 PM.
