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I broke my leg pretty badly a few months ago, and was incapable of driving. During this time my 2015 Smart ForTwo ED was in my parking garage. I can get around easier now and went out to check on it, and it's totally dead. I can unlock the driver's door manually with the key, but the charging port door is still locked. (Can't seem to re-lock the driver's door without power, either.)

It's parked at a charging station, so if I can get the port open I can give it the juice. But looking at some of the other posts here, it sounds like it may have ruined the battery? Is there a way to tell if the battery is done without special equipment?

Thanks for any help.
The first step is to charge, or jump from another car's battery in the conventional way, the 12V battery. It's behind the passenger side footwell and a foam block that contains the tire inflator/sealant kit. Even if the charge door wasn't locked, the high voltage battery cannot be charged until the 12V battery is charged. Unfortunately, due to a software design flaw, a failing 12V battery can cause the HV battery to self-destruct (the battery management module discharges the cells to zero) which effectively renders the Smart a brick if it is no longer under warranty. Maybe, jsut maybe, you will be lucky. Charge or jump the 12V battery right away!

The international hacker community has developed methods to restore Smarts that have been bricked in this way - but that is a topic for later.
 

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[see Thread: ED Long Term Storage]

Storage for up to 60 days (verified four times by myself):

1. DISconnect negative post, the (-) post, of 12v battery.
2. connect 12v battery to 'float charger" / "trickle charger".
3. when you return home REconnect 12v battery.
4. ED will operate normally with NO error codes or issues.
5. you have saved your high voltage battery from destruction by following this verified procedure, and saved currently $12,500.00US cost of hv battery replacement.
6. over 60 days - I have yet to vacate for this long so far, but maybe soon I will. But ask yourself, why would another month of disconnection make any
difference? When the car has no 12v energy source how can it create mayhem, injury, destruction to the System?
7. Report your findings to the 'Case Studies Needed - ED Long Term Storage' thread.
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Or, you can jsut disconnect the 12V battery after making sure it is fully charged. A healthy lead-acid battery should not self-discharge much over 60 days.

The current theory is that a "brownout" condition, from the dying 12 battery casues the BMS controller to send erronous "final dying commands" that turn on all the cell-balancing circuits which stay on and discharge the cells to near zero, becasue the cell balancing circuits are controlled by the BMS, but self-powered by the HV battery cells they manage, not the now-dead 12V battery.

Presumably the discharge process takes a few days, so if you discover the 12V battery died withing a couple days of it happening and immediately get the 12V syatem back up you can save the HV battery. That I why I strongly recommended that Ghost Lenin get his battery jumped or charged immediately.

But it appears that he might be one of those "one-post members" for whom we hear a cry for help for their bricked Smarts... then silence...
 
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