[GhostLenin]

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.

 

[MB DNA]

Welcome to SCoA.

Sounds as though BEST CASE, your 12V battery (passenger footwell) is dead. Until you have charged the battery you won’t have access to the charging port (HVSE) nor will you know the condition of the HV.

Unfortunately, this situation doesn’t bode well? Do keep us posted as to your findings.

 

[Yinzer]

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.

 

[Diasdk2m]

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.

If someone wanted to prevent this, how would one do so? By remplacing the 12v battery?
My car is not in storage. But the 12v has never been changed. I just don't want to wake up one day a have a brick.

 

[jwight]

As in any other car, 12v batteries eventually go bad, or are drained by various car systems if the battery is not kept charged. The easiest solution is to get a trickle charger for the 12v battery to maintain the charge if the car is not being driven regularly. If the battery is four or five years old, probably a good idea to have it load tested and replace if needed.

 

[sokoloff]

Past reports seem to indicate that non use of the car seems to be a factor. As stated above though, replacing an aging 12v battery is a reasonable consideration. I replaced one of my original six year old batteries this past spring. After six months of sitting on the shelf, the old battery it still reads 12.6v, so I certainly had some time left, but guessing wrong could be VERY costly. If the car was an ICE, I'd wait for it to tell me it needed to be replaced. That's dangerous with the ED..

Len
2014 EV Coupe 21,500 miles
2014 EV Cabriolet 21,500 miles

 

[Vincent Rapide]

In meantime to disconnect the battery as proposed by Vincent and add a charger for the 12V Battery longtime storage seams to me the most suitable solution. [JMK2020]

[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.
--

 

[Yinzer]

[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.
--

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...

 

[MB DNA]

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...

GL, hurry with some action towards reviving the 12V, every day of delay gets you closer to DOA!

 

[GhostLenin]

Sorry for not responding earlier, my leg is getting better but I'm still lacking in mobility which has hindered me from doing things myself. I had to wait until a friend could help me. First, we tried just connecting the jumper cables so I could unlock the charge port and plug it in. As expected I guess, nothing happened. The dash didn't light up and the charging station didn't indicate it was transferring power (normally a blue light turns on). So we took the 12v battery out and put it on a charger.

We're going to put it back in tonight and see if it will take a charge, but from what I have read my hopes aren't high. When I got home from the hospital I was in a tremendous amount of pain and on prescription narcotics for a while; tending to my car was the last thing on my mind. So I think it's probably been sitting there too long. I'll post again tonight or tomorrow with the results.

 

[GhostLenin]

Doesn't look good.

According to the battery charger, the 12v is fully charged. We reinstalled it and connected the main charger. The dash lights came on as usual, but it just said "Malfunction" above the charge meter, and the charging station light didn't turn on to indicate it was doing something. I waited several minutes with it plugged in, unplugged and tried again, same results.

Is that it then? I've seen 12k and 20k floated around as the price of a new battery, but I only paid ~6.5k for the car so I just can't see that being worth it.

 

[jzchen]

I wouldn’t repair a car that killed itself over a 12 V battery dying. Sadly I missed this thread. My immediate response would be to buy a replacement 12 V battery as first recourse. Just because you were able to get a trickle charger to raise the voltage up to where it says it’s full doesn’t necessarily mean the 12 V is now healthy. Might be worth investigating first whether the 12 V is truly in good shape and go from there.

 

[MB DNA]

GhostLenin said - “According to the battery charger, the 12v is fully charged.”

Not sure what that means? Green light vs. red, 12v or ?

Fully charged automotive batteries should measure at 12.6 volts or above. When the motor is running, this measurement should be 13.7 to 14.7 volts. smarts can be pretty demanding of a quality electrical supply.

If it was me I’d throw a new “fully charged” $150 battery at it BEFORE kicking $6.5k to the curb.

 

[Vincent Rapide]

Or, you can just disconnect the 12V battery after making sure it is fully charged. A healthy lead-acid battery should not self-discharge much over 60 days. [Yinzer]

Sorry, forgot to repeat that my 12v battery is old and thus needs the float charging while disconnected. Sure, a good 12v battery can sit for a month or three.
Next week taking another trip so Smarty will be on her own once again.
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