2008 E320 Bluetec Battery Drain...
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2008 E320 Bluetec
2008 E320 Bluetec Battery Drain...
I am sorry that my first post on this site is addressing an electrical issue...
2008 E320 Bluetec, Battery draining down in just a few days. Trying to isolate the issue.
I have put a meter in the battery ground circuit. .6 amps draw.
I have removed the small cable that bolts to the lug on the main POS battery cable clamp.
Disconnected the 4 red wires that leave the 'fuse block' close to the battery mounting location.
Pulled the 30 and 40 amp fuse in that same block.
The draw is still there.
I do not have a electrical diagram for the car but am leaning toward the fact that the POS batt cable leaves the trunk and goes to the starter and alternator.
Could yall give me any idea if I am on the right track??
On another note, with all of the electrics connected and car running, I am finding the relays the fuse block in the truck on the left side are pretty darn hot. Infared thermometer says 140-150 degrees. Seems a bit much.
Again, I apologize but would appreciate any help.
2008 E320 Bluetec, Battery draining down in just a few days. Trying to isolate the issue.
I have put a meter in the battery ground circuit. .6 amps draw.
I have removed the small cable that bolts to the lug on the main POS battery cable clamp.
Disconnected the 4 red wires that leave the 'fuse block' close to the battery mounting location.
Pulled the 30 and 40 amp fuse in that same block.
The draw is still there.
I do not have a electrical diagram for the car but am leaning toward the fact that the POS batt cable leaves the trunk and goes to the starter and alternator.
Could yall give me any idea if I am on the right track??
On another note, with all of the electrics connected and car running, I am finding the relays the fuse block in the truck on the left side are pretty darn hot. Infared thermometer says 140-150 degrees. Seems a bit much.
Again, I apologize but would appreciate any help.
MBWorld Fanatic!
Joined: May 2022
Posts: 1,917
Likes: 499
From: The Netherlands
2005 CLS55 AMG W219 C219
Posted this not to long ago here: https://mbworld.org/forums/e-class-w...ery-drain.html
I was also searching for parasitic drain. Some things:
- Search on Youtube, there are quite some videos on this topic, especially for W211
- Seat control modules are a common culprit, you can test this by pulling out the fuses and checking the draw
- Alarm siren is a common issue, with age the onboard batteries will fail to hold charge. The alarm siren will keep requesting current from the car, preventing it from sleep and draining the battery
- Audio Gateway is a common issue
- Navigation unit can cause drain
- Voltage regulator can cause drain
- BCM can cause drain
- AUX battery can cause drain
- AUX battery relay can cause drain
- non-MB Original alternator can cause issues! There was a thread in W211 AMG section not too long ago if memory serves me right
I replaced my BCM (2005 CLS W219) with a BCM from a 2007 E-class W211. Also replaced the AUX relay, alarm siren, both batteries. I disconnected all Tele Aid/Phone capabilities and fiber looped out the components I dont need (you also need to code them out).
I can also highly recommend a bluetooth battery guard, it gives insight what is happening with the battery > https://mbworld.org/forums/c219/8443...ml#post8860681
I was also searching for parasitic drain. Some things:
- Search on Youtube, there are quite some videos on this topic, especially for W211
- Seat control modules are a common culprit, you can test this by pulling out the fuses and checking the draw
- Alarm siren is a common issue, with age the onboard batteries will fail to hold charge. The alarm siren will keep requesting current from the car, preventing it from sleep and draining the battery
- Audio Gateway is a common issue
- Navigation unit can cause drain
- Voltage regulator can cause drain
- BCM can cause drain
- AUX battery can cause drain
- AUX battery relay can cause drain
- non-MB Original alternator can cause issues! There was a thread in W211 AMG section not too long ago if memory serves me right
I replaced my BCM (2005 CLS W219) with a BCM from a 2007 E-class W211. Also replaced the AUX relay, alarm siren, both batteries. I disconnected all Tele Aid/Phone capabilities and fiber looped out the components I dont need (you also need to code them out).
I can also highly recommend a bluetooth battery guard, it gives insight what is happening with the battery > https://mbworld.org/forums/c219/8443...ml#post8860681
