Battery Issues
Thread Starter
Member
Joined: Mar 2009
Posts: 124
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From: Bay Area, CA
2005 E55
Battery Issues
I have been getting the "low battery some convenience features disabled" message once a week. I have already replaced the aux battery which was at 10.5v. When I get the message I disconnect all leads to both batteries & the aux is 12.8v & the main is 12.4v. I have been in dyno mode for the last 2 weeks to monitor the voltage & it is always 11.9v before I start then 14.5-15v driving. It has never dropped below 13.7 when started & the 2 times I have received the low battery message I was already looking at the voltage on the instrument panel & it was at around 14v when the message came up.
Any ideas what it could be? It does seem the instrument lights do pulsate slightly. Maby voltage regulator? It seems like the alternator is working fine since the voltage does increase to 14.5-15 when driving
Any ideas what it could be? It does seem the instrument lights do pulsate slightly. Maby voltage regulator? It seems like the alternator is working fine since the voltage does increase to 14.5-15 when driving
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Joined: Oct 2006
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From: Caribbean/Florida/Colorado
E-ZGO 53hp., 1999 E 430 sport, 2004 E 55, 2008 Tahoe LTZ on 24"s
You need a new main /starter battery voltage should be 13.5.
Sounds like your charging system is operating fine.
If you continue to use your car with a old weak battery you will prematurely
wear out your alternator/voltage regulator.
FWIW on a car so electronically dependent, a low voltage condition is asking for
many other electrical problems, low voltage kills.
Sounds like your charging system is operating fine.
If you continue to use your car with a old weak battery you will prematurely
wear out your alternator/voltage regulator.
FWIW on a car so electronically dependent, a low voltage condition is asking for
many other electrical problems, low voltage kills.
Thread Starter
Member
Joined: Mar 2009
Posts: 124
Likes: 0
From: Bay Area, CA
2005 E55
You need a new main /starter battery voltage should be 13.5.
Sounds like your charging system is operating fine.
If you continue to use your car with a old weak battery you will prematurely
wear out your alternator/voltage regulator.
FWIW on a car so electronically dependent, a low voltage condition is asking for
many other electrical problems, low voltage kills.
Sounds like your charging system is operating fine.
If you continue to use your car with a old weak battery you will prematurely
wear out your alternator/voltage regulator.
FWIW on a car so electronically dependent, a low voltage condition is asking for
many other electrical problems, low voltage kills.
Super Member
Joined: Jun 2009
Posts: 845
Likes: 0
From: San Ramon, CA
A Prius because I'm green
Take it in and have the batteries tested, if they are good then it's the voltage regulator or alternator. This is a common problem and I had it as well. Get it fixed before you go down the road and it shuts your brakes off, which has happened recently to a member that I know on here.
Thread Starter
Member
Joined: Mar 2009
Posts: 124
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From: Bay Area, CA
2005 E55
It does look like it's the main battery. After I connected the cables I turned on the lights, rear defroster & hazards & then checked the main bat. It dropped to 11.1v, but the Aux stayed constant at 12.8v. When I started the engine the main battery tested at 13.5v. I am going to order one tomorrow.
Super Member
Joined: Jan 2008
Posts: 586
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From: Springfield, Missouri
03' E55 Techtite Grey
It does look like it's the main battery. After I connected the cables I turned on the lights, rear defroster & hazards & then checked the main bat. It dropped to 11.1v, but the Aux stayed constant at 12.8v. When I started the engine the main battery tested at 13.5v. I am going to order one tomorrow.
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Super Member
Joined: Apr 2009
Posts: 552
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From: Chicago suburbs
2004 E55 AMG
Go to Wal-Mart or Autozone. Either one should carry the large starter battery, and I believe most parts stores will have the smaller one(it's a common motorcycle size). I juts bought a brand new starter battery for under $80. If you want OEM then go to the dealer, but in all honesty, a battery is a battery, unless it's something like an Optima.
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Super Member
Joined: Jan 2008
Posts: 586
Likes: 2
From: Springfield, Missouri
03' E55 Techtite Grey
Go to Wal-Mart or Autozone. Either one should carry the large starter battery, and I believe most parts stores will have the smaller one(it's a common motorcycle size). I juts bought a brand new starter battery for under $80. If you want OEM then go to the dealer, but in all honesty, a battery is a battery, unless it's something like an Optima.
Stupid question but where is the little one located? I know the big one is in the trunk cause I've used it to jump start some people but I've never seen the little one.
Thread Starter
Member
Joined: Mar 2009
Posts: 124
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From: Bay Area, CA
2005 E55
To get into the dyno mode make sure the display is on the temp, then turn key 1 click & then quickly press the reset button 3 times. voltage level will come up.
I bought the aux battery which is on the passenger side under the air filter 10mm nut to release, from sears diehard 14 bs $89.
I bought the main battery from autozone for $139.
Everthing working good now. No pulsating headlights or interior lights anymore.
I bought the aux battery which is on the passenger side under the air filter 10mm nut to release, from sears diehard 14 bs $89.
I bought the main battery from autozone for $139.
Everthing working good now. No pulsating headlights or interior lights anymore.
Super Member
Joined: Jan 2008
Posts: 586
Likes: 2
From: Springfield, Missouri
03' E55 Techtite Grey
To get into the dyno mode make sure the display is on the temp, then turn key 1 click & then quickly press the reset button 3 times. voltage level will come up.
I bought the aux battery which is on the passenger side under the air filter 10mm nut to release, from sears diehard 14 bs $89.
I bought the main battery from autozone for $139.
Everthing working good now. No pulsating headlights or interior lights anymore.
I bought the aux battery which is on the passenger side under the air filter 10mm nut to release, from sears diehard 14 bs $89.
I bought the main battery from autozone for $139.
Everthing working good now. No pulsating headlights or interior lights anymore.
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From: The Villages, Florida
2006 E320 CDI
Super Member
Joined: Jan 2008
Posts: 586
Likes: 2
From: Springfield, Missouri
03' E55 Techtite Grey
Thread Starter
Member
Joined: Mar 2009
Posts: 124
Likes: 0
From: Bay Area, CA
2005 E55
