Help Needed: Voltage..What part to replace/test......
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Joined: Jul 2011
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E55
Help Needed: Voltage..What part to replace/test......
I've replaced the Aux battery, main battery, and the alternator within 3 months. Tonight I again got the "Visit Workshop" battery warning... My question is what else could it be and what/how would I test it. Thanks....
2005
E55
66K Miles
2005
E55
66K Miles
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From: Northern VA
W211
Battery isolator relay under the ps windshield. Or the battery control module in the trunk that is to the right of the trunk latch lock Had to replace those two along w new batteries and voltage regulator
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E55
Replaced both (the one in the trunk and in the engine compartment), now luck. The only change is now the convience features turn off and I get the "Visit Workshop- Battery) under hard acceleration. As well, while in dyno mode my voltage is this....
1.Key position #1- 12.2 Volts
2.Key positoin #2 - 12.0
2.After start (with air, lights, and seat cooler on) 12.2
1.Key position #1- 12.2 Volts
2.Key positoin #2 - 12.0
2.After start (with air, lights, and seat cooler on) 12.2
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From: Northern VA
W211
For me to get rid of the red batter visit workshop, i had to replace the battery isolator relay for it to go away. BEFORE that, i replaced the voltage regulator, and both batteries, but still had the RED battery code. Try and find one on ebay or buy from parts.com, they are around $135 i believe.
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From: West
2005 E55 Wagon
Replaced both (the one in the trunk and in the engine compartment), now luck. The only change is now the convience features turn off and I get the "Visit Workshop- Battery) under hard acceleration. As well, while in dyno mode my voltage is this....
1.Key position #1- 12.2 Volts
2.Key positoin #2 - 12.0
2.After start (with air, lights, and seat cooler on) 12.2
1.Key position #1- 12.2 Volts
2.Key positoin #2 - 12.0
2.After start (with air, lights, and seat cooler on) 12.2
Thread Starter
Junior Member
Joined: Jul 2011
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E55
I actually have 2 - 2005 E55's, so I was swaping parts to see what the problem may be. I swapped both battery's, battery isolator relay, and BCM. Yet still the same problem.. Next will be to take to Indy shop.... Thanks for the info..
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From: Phoenix by way of Texas
2003 E55 AMG
Be sure to chime back in with what ends up happening. I just replaced my alternator about a month or so ago and would hate to see the red visit workshop battery indicator again after swapping both batteries as well.
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MBWorld Fanatic!
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From: San Diego
2004 E55
There have been 3 (I think?) revisions to the Battery Control Module since it was introduced in the E55. When I was having battery problems - batteries dying quickly - I found that my BCM was not doing it's proper job. No problems since replacing with the latest iteration. However, I agree that getting it properly diagnosed will save time and money!
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From: Northern VA
W211
How long did you let the car run after doing this? It took my car over 5 min before the red battery code light when off.. Maybe some time for the ecu to adjust and do the checks....
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2004 E55 AMG
i experienced the visit workshop battery warning. it might be really obvious but make sure the connection to the terminal is very snug. mine was just a bit loose and after tightening no more light. worth a shot at least.
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From: Tampa
E55
Have you also checked the voltage while you were drive to see if it keeps dropping and going back up. I had a similar issue replaced the alternator then two week later I was getting the same lights. Replaced both battiers and same lights I replaced the front relay and BMC in trunk. Same thing it turned out to be a bad alternator had the alternator repaired instead of replaced again the rotor assembly was loose causing the alternator to charge then stop charging at different speeds when the belt was turing. Be carful with the refurb alternators
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From: West
2005 E55 Wagon
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From: Orlando
W211 E55 AMG Kompressor
Help!!!!
Hello everyone, can someone please provide some feedback on this tread, last night while idling my E55 in the garage I smelled a faint burning scent, popped the hood and could not find nor describe the source of this burning smell, however, after checking the forum on the matter it's come to my attention that the alternator/voltage regulator could be on it's way out, convienience message comes on and off now so i know there is low voltage (11.1v) sometimes a bit less, here's my question,,, if, it is the regulator thats bad, would I still get the burning smell???? Or is the burning smell a clear sign that the alternator itself is toasted internally....feedback please!!!!!!!
Hello everyone, can someone please provide some feedback on this tread, last night while idling my E55 in the garage I smelled a faint burning scent, popped the hood and could not find nor describe the source of this burning smell, however, after checking the forum on the matter it's come to my attention that the alternator/voltage regulator could be on it's way out, convienience message comes on and off now so i know there is low voltage (11.1v) sometimes a bit less, here's my question,,, if, it is the regulator thats bad, would I still get the burning smell???? Or is the burning smell a clear sign that the alternator itself is toasted internally....feedback please!!!!!!!
Junior Member
Joined: Jul 2011
Posts: 46
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From: Orlando
W211 E55 AMG Kompressor
Burning smell, Alt/VR ?????
Help!!!!
Hello everyone, can someone please provide some feedback on this tread, last night while idling my E55 in the garage I smelled a faint burning scent, popped the hood and could not find nor describe the source of this burning smell, however, after checking the forum on the matter it's come to my attention that the alternator/voltage regulator could be on it's way out, convienience message comes on and off now so i know there is low voltage (11.1v) sometimes a bit less, here's my question,,, if, it is the regulator thats bad, would I still get the burning smell???? Or is the burning smell a clear sign that the alternator itself is toasted internally....feedback please!!!!!!!
Hello everyone, can someone please provide some feedback on this tread, last night while idling my E55 in the garage I smelled a faint burning scent, popped the hood and could not find nor describe the source of this burning smell, however, after checking the forum on the matter it's come to my attention that the alternator/voltage regulator could be on it's way out, convienience message comes on and off now so i know there is low voltage (11.1v) sometimes a bit less, here's my question,,, if, it is the regulator thats bad, would I still get the burning smell???? Or is the burning smell a clear sign that the alternator itself is toasted internally....feedback please!!!!!!!
