SL/R230: Massive battery drain
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Junior Member
Joined: Oct 2021
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SL500 R230
Massive battery drain
Yesterday I drove car for like 20 minutes, got back, put charger on rear battery (1A). Today I found a dead battery, charger reads it at 6.4 voltage (continues to charge).
I noticed i get this drain when car is locked.
At my old place I had garage, I didn't locked car and it could stay weeks without discharging it...
With engine on, both batteries are over 14v
both batteries are new oem
I already removed fuse for alarm horn (I thought horn went bad), but drain is still there.
I noticed i get this drain when car is locked.
At my old place I had garage, I didn't locked car and it could stay weeks without discharging it...
With engine on, both batteries are over 14v
both batteries are new oem
I already removed fuse for alarm horn (I thought horn went bad), but drain is still there.
Last edited by stayalive; Feb 20, 2022 at 04:00 AM.
Super Member
Joined: Aug 2017
Posts: 520
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From: Scottsdale AZ
2015 SL550 & 2012 S550 4matic
It sounds like a parasitic battery draw. Many times it’s pumps like the PSE pump continuously running because of a leak. Do you have any dash lights or messages?
Visit I bought a power probe 4 to track down an issue on my Sclass. Fantastic tool albeit on the spendy side.
Visit I bought a power probe 4 to track down an issue on my Sclass. Fantastic tool albeit on the spendy side.
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SL500 R230
It sounds like a parasitic battery draw. Many times it’s pumps like the PSE pump continuously running because of a leak. Do you have any dash lights or messages?
Visit https://www.amazon.com/stores/PowerP...F?ref_=ast_bln
I bought a power probe 4 to track down an issue on my Sclass. Fantastic tool albeit on the spendy side.
Visit https://www.amazon.com/stores/PowerP...F?ref_=ast_bln
I bought a power probe 4 to track down an issue on my Sclass. Fantastic tool albeit on the spendy side.
Also, with car locked. Many fuses (rear) still gets 12v. I think it shouldn't
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SL500 R230
Although I have some codes which are old. For EZS Can not sending messages or smh and k57 relay
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From: North West England
SL500
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SL500 R230
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From: North West England
SL500
Are you sure you removed the correct fuse? F71 (diagram enclosed).
If you did remove correct fuse, pump should not run, and so it would seem like someone has re-wired the pump, which could again be your issue!
If you did remove correct fuse, pump should not run, and so it would seem like someone has re-wired the pump, which could again be your issue!
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SL500 R230
