Phantom drain question
Member
Joined: Feb 2025
Posts: 83
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Hello All,
New user here, low possibility because I think you have been holding car long time so you might notice before but I will just add another wild guess: Could it be software estimation issue due to day/night diff? i.e. You left car 84% estimate at 7C degree afternoon, but next morning 5 am range estimation updated to 82% at 2C degree but software decide to be conservative to increase range again when weather get hot again and only being updated back to 84 ish percent after you drive at similar temps?
New user here, low possibility because I think you have been holding car long time so you might notice before but I will just add another wild guess: Could it be software estimation issue due to day/night diff? i.e. You left car 84% estimate at 7C degree afternoon, but next morning 5 am range estimation updated to 82% at 2C degree but software decide to be conservative to increase range again when weather get hot again and only being updated back to 84 ish percent after you drive at similar temps?
Newbie
Joined: Feb 2025
Posts: 11
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Hello All,
New user here, low possibility because I think you have been holding car long time so you might notice before but I will just add another wild guess: Could it be software estimation issue due to day/night diff? i.e. You left car 84% estimate at 7C degree afternoon, but next morning 5 am range estimation updated to 82% at 2C degree but software decide to be conservative to increase range again when weather get hot again and only being updated back to 84 ish percent after you drive at similar temps?
New user here, low possibility because I think you have been holding car long time so you might notice before but I will just add another wild guess: Could it be software estimation issue due to day/night diff? i.e. You left car 84% estimate at 7C degree afternoon, but next morning 5 am range estimation updated to 82% at 2C degree but software decide to be conservative to increase range again when weather get hot again and only being updated back to 84 ish percent after you drive at similar temps?
Member
Joined: Feb 2025
Posts: 83
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Ok reporting an update yesterday left the car at @ 80% around 4 pm yesterday then last update on MB me app was around 5:30 pm , today morning updated again 6:53 am 78%, I figured MB app -> charging -> more details -> toggling eco mode on/off triggers status update. My usable battery 89 Kw so 2 percent a lot
I took some screenshots, mid March I have service meeting for another reason, I guess they suspected because suddenly my MB me showed 12V battery health check menu, I will also send them this thread, yeah thank you all & @ScottC2 for quick recognition of this issue.
I took some screenshots, mid March I have service meeting for another reason, I guess they suspected because suddenly my MB me showed 12V battery health check menu, I will also send them this thread, yeah thank you all & @ScottC2 for quick recognition of this issue.
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Joined: Nov 2013
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
Ok reporting an update yesterday left the car at @ 80% around 4 pm yesterday then last update on MB me app was around 5:30 pm , today morning updated again 6:53 am 78%, I figured MB app -> charging -> more details -> toggling eco mode on/off triggers status update. My usable battery 89 Kw so 2 percent a lot I took some screenshots, mid March I have service meeting for another reason, I guess they suspected because suddenly my MB me showed 12V battery health check menu, I will also send them this thread, yeah thank you all & @ScottC2 for quick recognition of this issue.
I took some screenshots, mid March I have service meeting for another reason, I guess they suspected because suddenly my MB me showed 12V battery health check menu, I will also send them this thread, yeah thank you all & @ScottC2 for quick recognition of this issue.
MBWorld God!
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MBWorld God!
Joined: Dec 2019
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This thread that was discussed, and the OP of that thread also commented in the current thread: https://mbworld.org/forums/eqs/90896...ll-parked.html
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Another thing is, there is a known issue with battery draining from a door module keeping the systems awake, that affects the R232 SL and C192 GT and a few others like W206 C, not sure if it affects the EQ line.
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Thread Starter
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Joined: Nov 2013
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
Brought my vehicle in yesterday to see what's going on with the 2%/day phantom drain. I'm picking the car up later today, and this is what was in the notes:
"26275 Performed quick test and found code: U116000: A bus keepawake unit was detected. Performed guided test and result of guided test to perform various control unit software updates. Performed Battery management system control unit software update. Performed HV charge port software update. Performed DC/DC Converter control unit software update. Performed EZS SCN Coding update. Performed 12v battery test and found 12v battery to PASS test. Cleared fault memory. Verified vehicle starts and operates as designed. Verified customer concern is no longer present."
"26275 Performed quick test and found code: U116000: A bus keepawake unit was detected. Performed guided test and result of guided test to perform various control unit software updates. Performed Battery management system control unit software update. Performed HV charge port software update. Performed DC/DC Converter control unit software update. Performed EZS SCN Coding update. Performed 12v battery test and found 12v battery to PASS test. Cleared fault memory. Verified vehicle starts and operates as designed. Verified customer concern is no longer present."
Super Member
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From: Sweden
2023 EQE SUV 500 4Matic
Brought my vehicle in yesterday to see what's going on with the 2%/day phantom drain. I'm picking the car up later today, and this is what was in the notes:
"26275 Performed quick test and found code: U116000: A bus keepawake unit was detected. Performed guided test and result of guided test to perform various control unit software updates. Performed Battery management system control unit software update. Performed HV charge port software update. Performed DC/DC Converter control unit software update. Performed EZS SCN Coding update. Performed 12v battery test and found 12v battery to PASS test. Cleared fault memory. Verified vehicle starts and operates as designed. Verified customer concern is no longer present."
"26275 Performed quick test and found code: U116000: A bus keepawake unit was detected. Performed guided test and result of guided test to perform various control unit software updates. Performed Battery management system control unit software update. Performed HV charge port software update. Performed DC/DC Converter control unit software update. Performed EZS SCN Coding update. Performed 12v battery test and found 12v battery to PASS test. Cleared fault memory. Verified vehicle starts and operates as designed. Verified customer concern is no longer present."
Did they speculate as to what might have caused the "bus keepawake" code? I must admit, I'm skeptical about their response, if nothing else that you are aware of changed leading up to this. Perhaps it was an undocumented/unmentioned OTA update of some sort??
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
Interesting. I hope your "concern" continues to no longer be present!
Did they speculate as to what might have caused the "bus keepawake" code? I must admit, I'm skeptical about their response, if nothing else that you are aware of changed leading up to this. Perhaps it was an undocumented/unmentioned OTA update of some sort??
Did they speculate as to what might have caused the "bus keepawake" code? I must admit, I'm skeptical about their response, if nothing else that you are aware of changed leading up to this. Perhaps it was an undocumented/unmentioned OTA update of some sort??
If this does continue, I will ask them to replace the 12V, they did just send a $100-off coupon, though who knows what they'd charge for the replacement. If it were a combustion car, I'd have no issues changing the 12V myself, but I don't know what is needed on a BEV to keep things happy, so we'll see if I have to go through that route.
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Thank you @bytemaster0 sharing your experience, I will also add an update how it will go with myn in 2 week, first time I will be at service, should I ask tem any specific question to get the similar information you have provided or its usual report for service control?
Thread Starter
MBWorld Fanatic!
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
Thank you @bytemaster0 sharing your experience, I will also add an update how it will go with myn in 2 week, first time I will be at service, should I ask tem any specific question to get the similar information you have provided or its usual report for service control?
Thread Starter
MBWorld Fanatic!
Joined: Nov 2013
Posts: 1,030
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
Okay, so problem not solved. Rats. Still 2% drain overnight. Gonna see what they quote me for a new battery, but I'm going to try to push for a warranty replacement. Too much range loss overnight.
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Sorry for that, first when I notice I also have this issue i didnt mind much but given a second tought today if its constant 2% you do 1 extra charging cycle every month, high volt. battery life also measured by cycle count as well. Today is 8C here, i will see if it will slow down or stop and tomorrow disconnect dashcam download offline maps and turnoff any unnecessary service like location sharing etc... and monitor again but weather will be even more hot so it will be hard to blame anything if I dont get drop. Their board developer kit peak usage 200w I guess they managed to get close to half on prod. board so 60w on idle maybe a bit much, maybe some unusual or dirty sensor data keep forcing system to re-evaluate its status but i am just speculating and this system has logs, also it supports voltage monitoring , shame we can not access or the dealer, it would be quick to pinpoint. If your 12 V really healthly now I have more questions its mean something unkown doing constant drain even 12V can not keep it up? or maybe they run some temp. background diagnostic on some cars at this period? or dealer failed to recognize 12V battery issue similar to eqsowner experience. Maybe you can ask them to put a test battery temporarly for few days to prove it they are right?
its mean something unkown doing constant drain even 12V can not keep it up? or maybe they run some temp. background diagnostic on some cars at this period? or dealer failed to recognize 12V battery issue similar to eqsowner experience. Maybe you can ask them to put a test battery temporarly for few days to prove it they are right?
Thread Starter
MBWorld Fanatic!
Joined: Nov 2013
Posts: 1,030
Likes: 492
From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
Sorry for that, first when I notice I also have this issue i didnt mind much but given a second tought today if its constant 2% you do 1 extra charging cycle every month, high volt. battery life also measured by cycle count as well. Today is 8C here, i will see if it will slow down or stop and tomorrow disconnect dashcam download offline maps and turnoff any unnecessary service like location sharing etc... and monitor again but weather will be even more hot so it will be hard to blame anything if I dont get drop. Their board developer kit peak usage 200w I guess they managed to get close to half on prod. board so 60w on idle maybe a bit much, maybe some unusual or dirty sensor data keep forcing system to re-evaluate its status but i am just speculating and this system has logs, also it supports voltage monitoring , shame we can not access or the dealer, it would be quick to pinpoint. If your 12 V really healthly now I have more questions its mean something unkown doing constant drain even 12V can not keep it up? or maybe they run some temp. background diagnostic on some cars at this period? or dealer failed to recognize 12V battery issue similar to eqsowner experience. Maybe you can ask them to put a test battery temporarly for few days to prove it they are right?
its mean something unkown doing constant drain even 12V can not keep it up? or maybe they run some temp. background diagnostic on some cars at this period? or dealer failed to recognize 12V battery issue similar to eqsowner experience. Maybe you can ask them to put a test battery temporarly for few days to prove it they are right?
Thread Starter
MBWorld Fanatic!
Joined: Nov 2013
Posts: 1,030
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
Paid $300 this morning for a new 12V battery and 1/2 hour of labor. I had a $100 coupon for "any repair" that had been sent a few weeks earlier, which I used to get that price. Already I've noticed some results - my energy efficiency has improved significantly during highway travel, back to normal. I was seeing about 20Wh/mi more energy consumption with the old 12V battery. Also, the locking mechanism that locks the charging gun in place now works correctly - it wouldn't quite close every time I would plug in, and now the motor finishes locking every time. When I had the car in for the Bus Keepawake code, they noted that my 12V battery was 74% charged, which I found unusual given that the car had just been charged several times the day before. A good 12V battery should have been at a higher charge state.
I'm slightly miffed that I had to pay out of pocket - MB's criteria for evaluating a battery is clearly outdated for EVs, or so it would seem. I have no confirmation that my drain has been reduced, but I'm feeling much more optimistic this time. I'll report back tomorrow, but I think this will be the fix. Also, on a funny note, when I went to get in the car, the trunk release stopped working. I could open it from the inside, or from the key fob, but the emblem button was completely unresponsive. Tech took it back, and as soon as he parked it, the button began working again. He reflashed the software on the control module just in case, and of course now it's all working right, but still a funny little side quest.
Anyway, I'll post back tomorrow with, hopefully, a still-80%-charged battery!
I'm slightly miffed that I had to pay out of pocket - MB's criteria for evaluating a battery is clearly outdated for EVs, or so it would seem. I have no confirmation that my drain has been reduced, but I'm feeling much more optimistic this time. I'll report back tomorrow, but I think this will be the fix. Also, on a funny note, when I went to get in the car, the trunk release stopped working. I could open it from the inside, or from the key fob, but the emblem button was completely unresponsive. Tech took it back, and as soon as he parked it, the button began working again. He reflashed the software on the control module just in case, and of course now it's all working right, but still a funny little side quest.
Anyway, I'll post back tomorrow with, hopefully, a still-80%-charged battery!
Thread Starter
MBWorld Fanatic!
Joined: Nov 2013
Posts: 1,030
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
As a side note, I do wonder if this issue will not happen in the future, as it seems clear that at least on currently-flashed firmwares, the car will attempt to keep the 12V battery charged.
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Paid $300 this morning for a new 12V battery and 1/2 hour of labor. I had a $100 coupon for "any repair" that had been sent a few weeks earlier, which I used to get that price. Already I've noticed some results - my energy efficiency has improved significantly during highway travel, back to normal. I was seeing about 20Wh/mi more energy consumption with the old 12V battery. Also, the locking mechanism that locks the charging gun in place now works correctly - it wouldn't quite close every time I would plug in, and now the motor finishes locking every time. When I had the car in for the Bus Keepawake code, they noted that my 12V battery was 74% charged, which I found unusual given that the car had just been charged several times the day before. A good 12V battery should have been at a higher charge state.
I'm slightly miffed that I had to pay out of pocket - MB's criteria for evaluating a battery is clearly outdated for EVs, or so it would seem. I have no confirmation that my drain has been reduced, but I'm feeling much more optimistic this time. I'll report back tomorrow, but I think this will be the fix. Also, on a funny note, when I went to get in the car, the trunk release stopped working. I could open it from the inside, or from the key fob, but the emblem button was completely unresponsive. Tech took it back, and as soon as he parked it, the button began working again. He reflashed the software on the control module just in case, and of course now it's all working right, but still a funny little side quest.
Anyway, I'll post back tomorrow with, hopefully, a still-80%-charged battery!
I'm slightly miffed that I had to pay out of pocket - MB's criteria for evaluating a battery is clearly outdated for EVs, or so it would seem. I have no confirmation that my drain has been reduced, but I'm feeling much more optimistic this time. I'll report back tomorrow, but I think this will be the fix. Also, on a funny note, when I went to get in the car, the trunk release stopped working. I could open it from the inside, or from the key fob, but the emblem button was completely unresponsive. Tech took it back, and as soon as he parked it, the button began working again. He reflashed the software on the control module just in case, and of course now it's all working right, but still a funny little side quest.
Anyway, I'll post back tomorrow with, hopefully, a still-80%-charged battery!
Thread Starter
MBWorld Fanatic!
Joined: Nov 2013
Posts: 1,030
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
Bad news. Still draining. 2% in less than 24 hours, again. I'm out of ideas. Maybe the original battery was totally fine. Or maybe the replacement has been sitting too long. I just don't know what to think now.
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From: Sweden
2023 EQE SUV 500 4Matic
I forgot - have you let the car sit overnight with less than 20% charge on the HV battery, just in case a BMS recalibration might be relevant?
