2nd Car battery and still dying
Thread Starter
Junior Member
Joined: Oct 2016
Posts: 69
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From: Katy,Texas
03 CLK 320 A209
2nd Car battery and still dying
Not sure what is going on i replaced the prior battery my car had with a new one because the old one got a bad cell out of always dying, and then when i bought a new one it lasted for 3 days then it died as well i dont know whats going on i checked all the fuses ans they seem to be fine yet i keep losing power and the worst thing about i cant even put this car on neutral when battery is dead. What could be causing my battery to be dying consistently i have to charge it everyday now to turn on my car.
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CLK55 W209, CL63 W216
Hmm your sentences are like 3 for the punctuation of 1. Pretty good discount right there.
You obviously have a drain somewhere. Check what the drain actually is and then start pulling fuses. You can isolate the culprit eventually.
Also, you can shift gears without a battery by inserting a long screwdriver in the center console gap to hit the override.
You obviously have a drain somewhere. Check what the drain actually is and then start pulling fuses. You can isolate the culprit eventually.
Also, you can shift gears without a battery by inserting a long screwdriver in the center console gap to hit the override.
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Joined: Jan 2016
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From: New Jersey, USA
2006 Mercedes-Benz CLK500 Convertible
I would suggest 2 more things to consider. Once I was told in an auto shop.
1. Maybe your serpentine belt is loose (or worn) and there is not enough friction to spin alternator fast enough to charge.
2. Alternator failure?
Just my $0.02.
1. Maybe your serpentine belt is loose (or worn) and there is not enough friction to spin alternator fast enough to charge.
2. Alternator failure?
Just my $0.02.
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CLK55 W209, CL63 W216
Indeed. I guess I just assumed they checked the basics...battery and alternator, cables, belts etc.
Thread Starter
Junior Member
Joined: Oct 2016
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From: Katy,Texas
03 CLK 320 A209
Well no i haven't check either of those, how would i check those? I'm no pro mechanic thats why im here seeking help. From what i see the belt is fine and on there, but if its the alternator can someone direct me to where i can get it cheaper than what it is, i just spent a crap ton on other repairs for this car so thats why im asking.
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From: Atlanta Metro
2008 clk550 - Navigator - Frontier
Rodney has given the voltage ranges for when the car is off vs at idle. I can't recall what they are but you can search on battery or alternator and Rodney. You will need a voltmeter.
You might also borrow or buy a trickle charger and charge the battery for 12 hours or so and see if things stop working over the next 8 hours (lights, etc.) and a couple startups. If it dies w/o driving it is the battery or a drain on the battery.
If it works fine while testing in the garage but dies under regular use, it is probably the alternator.
Research Rodney's many replies on checking the battery.
Good luck....
You might also borrow or buy a trickle charger and charge the battery for 12 hours or so and see if things stop working over the next 8 hours (lights, etc.) and a couple startups. If it dies w/o driving it is the battery or a drain on the battery.
If it works fine while testing in the garage but dies under regular use, it is probably the alternator.
Research Rodney's many replies on checking the battery.
Good luck....
Thread Starter
Junior Member
Joined: Oct 2016
Posts: 69
Likes: 0
From: Katy,Texas
03 CLK 320 A209
Rodney has given the voltage ranges for when the car is off vs at idle. I can't recall what they are but you can search on battery or alternator and Rodney. You will need a voltmeter.
You might also borrow or buy a trickle charger and charge the battery for 12 hours or so and see if things stop working over the next 8 hours (lights, etc.) and a couple startups. If it dies w/o driving it is the battery or a drain on the battery.
If it works fine while testing in the garage but dies under regular use, it is probably the alternator.
Research Rodney's many replies on checking the battery.
Good luck....
You might also borrow or buy a trickle charger and charge the battery for 12 hours or so and see if things stop working over the next 8 hours (lights, etc.) and a couple startups. If it dies w/o driving it is the battery or a drain on the battery.
If it works fine while testing in the garage but dies under regular use, it is probably the alternator.
Research Rodney's many replies on checking the battery.
Good luck....
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It's 12.6v at rest, no less than 11v during cranking, and 14v at idle. That's just the general rule of thumb. If those readings are low, then you need to get the system checked. For example, if the at-rest is 11.8v, then it could be a bad battery, but it could also be an electrical consumer draining it. If it goes down to 10v during cranking, it could be a bad battery or a bad alternator, or even something more serious like engine or transmission problems. If your idle voltage is low, then you may have as bad alternator, but then again, a bad battery can act like a giant resistor and drag down the voltage. So, check it out, and if it's not to spec, dig deeper with proper diagnostic procedures and equipment.
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Thread Starter
Junior Member
Joined: Oct 2016
Posts: 69
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From: Katy,Texas
03 CLK 320 A209
yup just checked and its saying the battery is at 3.7v while car is off and cold, the alarm didnt unlock the car, i connected a baterry charger and it said battery is on 0% with 3.7v and the the alternator is low.
Thread Starter
Junior Member
Joined: Oct 2016
Posts: 69
Likes: 0
From: Katy,Texas
03 CLK 320 A209
It's 12.6v at rest, no less than 11v during cranking, and 14v at idle. That's just the general rule of thumb. If those readings are low, then you need to get the system checked. For example, if the at-rest is 11.8v, then it could be a bad battery, but it could also be an electrical consumer draining it. If it goes down to 10v during cranking, it could be a bad battery or a bad alternator, or even something more serious like engine or transmission problems. If your idle voltage is low, then you may have as bad alternator, but then again, a bad battery can act like a giant resistor and drag down the voltage. So, check it out, and if it's not to spec, dig deeper with proper diagnostic procedures and equipment.
Senior Member
Joined: Sep 2009
Posts: 364
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From: Washington, DC
2007 Mercedes CLK63 AMG
I had a similar problem where I had a battery drain consistently. The culprit turned out to be the alarm buzzer. Once replaced with a fresh one no problems.
Another option might be some electrics - i.e. COMAND not shutting off after you lock and it keeps running - this also happened to me and all I had to do is remove the navigation DVD to put it to sleep. This again is from my experience. But the fact that the battery drains down to 3.7V points to the fact that something running at that voltage is what drains it - i.e. something not going to sleep.
Another option might be some electrics - i.e. COMAND not shutting off after you lock and it keeps running - this also happened to me and all I had to do is remove the navigation DVD to put it to sleep. This again is from my experience. But the fact that the battery drains down to 3.7V points to the fact that something running at that voltage is what drains it - i.e. something not going to sleep.
Senior Member
Joined: Sep 2009
Posts: 364
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From: Washington, DC
2007 Mercedes CLK63 AMG
As a further explanation...stick around your car for a while after locking it with the alarm armed. If you see your lights going on and off it means you have a dead built-in alarm battery and you need a new alarm. It's located in the passenger side wheel well.
