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ESS: Extremely Low. Begin Charging ASAP.

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This was the message I got on the display today, battery seems to be at 0 %. The strange thing is that two days ago after parking the car, I opened the trunk and removed the power plug that I assumed would completely shutdown the car, and then the battery was at around 24%. So the battery should not drop 24 %??? Anyone knows what is going on please?

I have previously reported that the car would sometimes not go to sleep and drain the battery when parked and not plugged in:
Roadster Radio not working and past few days Battery life dropping 5% per day :( - Page 4

After the "ESS: Extremely Low. Begin Charging ASAP.", next was "SWP: Aux Battery Supply Low". Would replacing the 12 volts battery fix this issue?
I also got "VMS: Battery Discharging During Charge" and charging stopped, but I tried again and then charging seemed to work, so right now the car is hopefully charging.
 
This was the message I got on the display today, battery seems to be at 0 %. The strange thing is that two days ago after parking the car, I opened the trunk and removed the power plug that I assumed would completely shutdown the car, and then the battery was at around 24%. So the battery should not drop 24 %??? Anyone knows what is going on please?

I have previously reported that the car would sometimes not go to sleep and drain the battery when parked and not plugged in:
Roadster Radio not working and past few days Battery life dropping 5% per day :( - Page 4

After the "ESS: Extremely Low. Begin Charging ASAP.", next was "SWP: Aux Battery Supply Low". Would replacing the 12 volts battery fix this issue?
I also got "VMS: Battery Discharging During Charge" and charging stopped, but I tried again and then charging seemed to work, so right now the car is hopefully charging.

Wait you pulled the ESS's orange service disconnect and plugged it back in later and it still drained significantly in that time? if yes, you have an serious issues within the ESS.

I looked at your older posted ahr.log, bricks looked fairly close to each other, can you post a new log?
 
Just curious why the Roadster sat at 24%? They don't like sitting at a low SOC and you should always at least pull it up to 35-40% minimum. If you know its going to be sitting for a few days then 50-65%. If I take my Roadster on a long trip I make sure to do two things if time/location permits:
1) Do a cooldown of the ESS to drive the temps down to 26C.
2) Pull the SOC up if its below 37% to 40+%

Where are you located? Are temps high? If the temps are high in the ESS, the cooling pump will keep running all night and day until it drops down to a temp it feels won't harm the pack. Now you said you pulled the ESS fuse, so that sounds very odd. There should be nothing external of the ESS that's pulling juice and if your SOC is dropping then something bad has failed internally which is causing this excessive drain.

Definitely get into Tesla ASAP, also review your logs.
 
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This leakage should be located and fixed by Service.

Have you tried Storage Mode? SM would seem to imply 'no accessories' so might be a good choice to make right now.

Clarify exactly what you did re: trunk/ power plug?
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Wait you pulled the ESS's orange service disconnect and plugged it back in later and it still drained significantly in that time? if yes, you have an serious issues within the ESS.

I looked at your older posted ahr.log, bricks looked fairly close to each other, can you post a new log?

Yes, I pulled the ESS's orange service disconnect. It was to make sure the battery would not drain anymore, I hoped....
I'm located in Norway, temperature is maximum 20C these days. Thanks for the battery advice, the cooling pump seems to run all the time. Can that drain as much as 200 Watts? If yes, that could explain the 5 kWh per day drain I saw before unplugging the orange service disconnect.
I try to be very gentle with the battery (don't run cooldown though because I haven't the latest firmware on the OVMS yet). But this summer I rented out the car to a lady, and unfortunately the log file is missing some of that history.
During that rent, the brake pump was full of water and had to be changed because the lady didn't have enough feet-power to brake without this system working (the Top Gear also had problems with that...). Do you think it was cleaning or driving through deep water that caused this?
Perhaps water has entered the battery as well? I once got an error message indicating some error with the battery insulation, right after I got the car back about a month ago, but haven't seen it again.

For flipping the pump Tesla Service Oslo charged 1570 USD (I found the same vacum pump listed on the web for less than 500 USD and I think it is very simple to change it). I told Tesla service for the fifth of sixth time about the battery draining problems I have had for years, but they didn't have time to look at it and asked me to get back for a full check. For $200 per hour, which is what service charge here, I'm not looking forward to that.

This is the latest log file taken two days ago, right before the orange plug disconnect:
https://dl.dropboxusercontent.com/u/96793917/201409051553.tar

Screenshot from the excellent TeslaFlux app showing how battery drops while car is parked and not plugged in:
https://dl.dropboxusercontent.com/u/96793917/BatteryLooses10percentInOneDay.jpg

From 2011 during a happy period when battery was not discharged:
https://dl.dropboxusercontent.com/u/96793917/From27.10.2011-27Days-BatteryDoesNotDischarge.jpg

From 2012 when the battery did discharge:
https://dl.dropboxusercontent.com/u/96793917/From04.29.2012-30Days-BatteryDoesDischarge.jpg

From 2013, note the 100 % SOC decreasing very fast at the beginning of the lower plot and the ESS temp going crazy at the end of the upper plot, please explain what is going on:
[url="https://dl.dropboxusercontent.com/u/96793917/From04.29.2012-30Days-BatteryDoesDischarge.jpg"]https://dl.dropboxusercontent.com/u/96793917/From04.29.2012-30Days-BatteryDoesDischarge.jpg
[/URL]
The car is now charging. I will try service mode and contact Tesla Service Trondheim. Thanks a lot for the valuable support!
 
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I'm located in Norway, temperature is maximum 20C these days. Thanks for the battery advice, the cooling pump seems to run all the time. Can that drain as much as 200 Watts?


Ok, Norway. You should put that in your profile, helps people out helping you. Well @20C your cooling pump should not be running "all the time". Most it should run is approx 5-10Mins max (don't know exact but not long) when you do a "wake" action (opening the door, locking/unlocking, etc.) before falling back asleep. Pump runs whenever the Roadster wakes from sleep from these actions. When I run the "manual" cool down I target 26C. I don't have OVMS re-connected but I just put the Roadster on a low amp charge and monitor the ESS temps, once 26C has been reached I shut down the charge. I don't know the cutoff, however I think the ESS temps need to be above 35C to have the pump run continuously. Bottom line... your pump should not be running 24/7. So with the Roadster not sleeping and running the pump running all the time, it will drain the battery source pretty good. Make sure to pass that data on to Tesla. I know service is expensive, however be greatful that the Roadster due to be

As for water in your brake reservoir (pump as you call it), if you haven't flushed out your system after 2 years it will build up water in there. First sign is a murky dark brake fluid color. Brake fluid should be very clear and consistent. I don't think the Roadster went through deep water submerging components ( I believe that's what you implied.)
 
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SWP: Aux Battery Supply Low
if your car is 2.0/2.5 the 12v battery get charged by the ESS when it's on, it was low when you replugged back in the ESS service disconnect.

Yes, I pulled the ESS's orange service disconnect. It was to make sure the battery would not drain anymore, I hoped....
Just making 100% sure, you pulled the service disconnect from this port right?
Capture.PNG

Looking at the log right before you said you pulled the ESS service disconnect showed the ESS around 50% SOC, btw there is a SOC delta of 8% between the bricks.
The ESS orange service disconnect should stop the heater/pump/HVAC/etc. You shouldn't have seen any loss of SOC, something really amiss, did you hear the cooling pump turn on at all in that time (it shouldn't have). Also did you see any other car activity? is VMS/VDS still on?

the cooling pump seems to run all the time. ...

Well if it gets cold enough the heater and coolant pump will kick on, but at 20c I'm guessing it's not that.
The pump should turn off after a 10-15 mins if you leave car alone (i.e. don't open trunk or doors), it's it not turning off then that's likely your problem.
 
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Yes, I unplugged the plug pictured above. I usually do this to stop the battery from draining when I'm not able to find an electricity outlet for days, and it has worked before, the last time did it was some months ago.

We had the warmest summer ever here, still cold compared to California, but not reaching the limit where the battery heater should start.

The car is now fully charged in standard mode, reported: 12 hours charging @ 16 amp, ca 237 Volts using 44 kWh. 264 km ideal range. CAC: 138.71 Ah.
 
I just looked at your log images you linked, it's odd that during the voltage drop there seems to be no PEM temp C data on the chart. If your VDS is in service mode, I would verify the ESS temp matches that chart.

Anyways if your loosing a constant 200watts continuously, only thing to me that adds up to those numbers would be coolant pump and DC-DC converter always being online. How old is your 12v battery could be bad? should check it out.

Also if you verified the coolant pump does turn off and isn't the problem, my next step would be using a thermal imaging camera (Flir E4 or one) and check for hot spots in/around/under/etc the car. As ~200 watts heat generated should be noticeable on the camera.
 
I just looked at your log images you linked, it's odd that during the voltage drop there seems to be no PEM temp C data on the chart. If your VDS is in service mode, I would verify the ESS temp matches that chart.

True, strange that the ESS temp C data is not displayed when car is discharging so fast. Here is a link showing the ESS temp C data reach >100 C in the upper plot and SOC decreasing very fast at the beginning of the lower plot:
https://dl.dropboxusercontent.com/u/96793917/From24.12.2013-29Days.jpg

Anyways if your loosing a constant 200watts continuously, only thing to me that adds up to those numbers would be coolant pump and DC-DC converter always being online. How old is your 12v battery could be bad? should check it out.

I agree, replaced it about 2 years ago. Have an extra so will replace it.

Also if you verified the coolant pump does turn off and isn't the problem, my next step would be using a thermal imaging camera (Flir E4 or one) and check for hot spots in/around/under/etc the car. As ~200 watts heat generated should be noticeable on the camera.
Good suggestion.
 
This was the message I got on the display today, battery seems to be at 0 %. The strange thing is that two days ago after parking the car, I opened the trunk and removed the power plug that I assumed would completely shutdown the car, and then the battery was at around 24%. So the battery should not drop 24 %??? Anyone knows what is going on please?
When I had my car in for it's annual service, my OVMS sent a few emergency texts that the ESS was at 0%. It happened when they pulled the power plug. My guess is, with that plug pulled, the car isn't talking the battery anymore. Have you plugged it back in to verify the charge? I doubt this is a real problem; just the car reporting that there's no battery connected.
 
When I had my car in for it's annual service, my OVMS sent a few emergency texts that the ESS was at 0%. It happened when they pulled the power plug. My guess is, with that plug pulled, the car isn't talking the battery anymore. Have you plugged it back in to verify the charge? I doubt this is a real problem; just the car reporting that there's no battery connected.

Thanks, I think this is what happened. I have connected this plug several times after this happened and never got the same. I have seen a message asking to wait for 2 minutes after plugging, probably I didn't wait.