Battery drain W208 CLK55
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Junior Member
Joined: Sep 2011
Posts: 36
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From: Dubai
2001 CLK55 AMG
Battery drain W208 CLK55
Hi all,
I've had a battery drain problem for the past 2 years or so on my 2001 CLK55, and I've had no luck solving it.
If I don't drive the car for a couple of days, the battery goes low, and doesn't have enough juice to crank the engine. I've been through 3 batteries, the last on bought a few months ago, which is in good condition, as I was driving 120km per day working on my last project.
Now I don't drive as much (I work at home these days), so I have time to try to resolve this.
I used an ammeter and measured the current when the car is locked, and alarm active. The current settled down to around 50mA. It was the same for 30 minutes. This suggests that something is acting erratically, and consuming current randomly, which is very hard to trace!
I did a lot of research, and came across a common problem with the alarm siren battery, where the battery fails and can cause erratic current consumption. I disconnected this yesterday, however, this morning (20 hours later), the battery voltage had dropped 0.7V, from 12.7 down to 12, so it appears the siren isn't to blame.
Another common problem is the seat controllers. However, my understanding is that if one is faulty there would be a 700mA draw constantly, so it appears that this isn't the problem.
I also removed the fuse for the phone, but this didn't resolve it either.
Anyone any ideas or thoughts?
Cheers
DXBStew
I've had a battery drain problem for the past 2 years or so on my 2001 CLK55, and I've had no luck solving it.
If I don't drive the car for a couple of days, the battery goes low, and doesn't have enough juice to crank the engine. I've been through 3 batteries, the last on bought a few months ago, which is in good condition, as I was driving 120km per day working on my last project.
Now I don't drive as much (I work at home these days), so I have time to try to resolve this.
I used an ammeter and measured the current when the car is locked, and alarm active. The current settled down to around 50mA. It was the same for 30 minutes. This suggests that something is acting erratically, and consuming current randomly, which is very hard to trace!
I did a lot of research, and came across a common problem with the alarm siren battery, where the battery fails and can cause erratic current consumption. I disconnected this yesterday, however, this morning (20 hours later), the battery voltage had dropped 0.7V, from 12.7 down to 12, so it appears the siren isn't to blame.
Another common problem is the seat controllers. However, my understanding is that if one is faulty there would be a 700mA draw constantly, so it appears that this isn't the problem.
I also removed the fuse for the phone, but this didn't resolve it either.
Anyone any ideas or thoughts?
Cheers
DXBStew
MBWorld Fanatic!
Joined: Oct 2012
Posts: 1,427
Likes: 100
From: Florida
2002 CLK 55 AMG cabriolet Eurocharged
The alternator voltage regulator was first thought, next a battery going stale.
These problems get complicated on the internet. the more information and tests performed will help a lot.
Start simple having the battery load tested first.
These problems get complicated on the internet. the more information and tests performed will help a lot.
Start simple having the battery load tested first.
