Completely no power response after not using for three weeks

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lingandshow

Member
Joined
Sep 23, 2014
Messages
6
Hello All. I just got back from three weeks of vacation and found that I can not start the car anymore.
The car was plugged in through out this period of time in the garage. When I opened the (unlocked) doors, the cabin light did not come on. There was also no any response after inserting and turning the key fob. The four doors do not respond to the remote, and both the lift gate and the exterior charger port cover do not open.
Please kindly advise. Thank you.
 
Sounds like your 12v battery is drained. This happened several times on the FFE I used to have, and twice on the Volt, typically after they've been sitting for a while. Everything that runs off of the 12v battery is dead (lights, power locks, etc), even though the HV battery is charged.

Follow the jump starting instructions in the owner's manual, and you should be fine (page 269-270 in the online manual on this forum). Let us know how it goes...
 
Sounds right. Also, please take a picture of the 12V battery so we all can see what it looks like. Good luck and thanks.
 
Jump-starting the 12V battery worked! Thank you guys! :D

A few notes:

- Please refer to the attached image of the "engine bay". According to the manual, to jump-start the car, the red jumper cable is to connect to the port under the red cap on the right. But the AAA tow truck driver thought it should be the port under the red cap on the left, and he charged through this port and it worked. This left block looks more similar to a traditional 12V battery.

MB%20B%20Class%20ED.jpg


- Due to the complete loss of the 12V battery power, besides that the date/time information was reset, an error signal related to memory loss also came up when I tried to use the GPS function. The previously saved destinations and histories are all intact. The one difference I noticed is that the scale bar and distance in GPS guiding (both the text and voice) changed to the metric system (using m/km rather than ft/mile). The speed limit is still in mile/hour. I cant seem to find the option to change this setting though.
 
L&S,

Beware. When this happened in my gas MB, after the jump start, all sorts of weird stuff happened. To name some, the transmission fritzed out and a module had to be replaced. The sun roof would not operate (not applicable here). There were other stuff so be careful for a few days.

Thanks for the picture.
 
lingandshow said:
The one difference I noticed is that the scale bar and distance in GPS guiding (both the text and voice) changed to the metric system (using m/km rather than ft/mile). The speed limit is still in mile/hour. I cant seem to find the option to change this setting though.
In case you haven't tried it yet, page 187 in the manual says how to set the units. It's done through the instrument cluster display. Manual is kinda misleading on how to change/save the setting. Cut/pasted below, with clarification in bold red:

Press the right or left button on the steering wheel to select the Sett menu.
Press the up or down button to select the Instrument Cluster submenu.
Press the OK button to confirm.
Press the up or down button to select the Display Unit Speed-/Odometer function.
You will see the selected setting: km or miles.
Press the OK button to change the setting.
Pressing the OK button repeatedly will alternate between miles and km.
The displayed setting is automatically saved.


The selected unit of measurement for distance applies to:
  • the digital speedometer in the Trip menu
    the odometer and the trip odometer
    the trip computer
    the current consumption and the range
    navigation instructions in the Navi menu
    cruise control
    ASSYST PLUS service interval display


Again, good luck!
 
interesting - why would a deep cycle automotive 12v battery fail after 3 weeks - and

why would you not use the L-ion rechargeable as a back up source of 12v power?

All you need is a capacitor and a resistor circuit. . . . and a switch.
 
I believe the main reason they don't use the LION battery as a backup is because the electronics that control voltage change are actually powered by the 12v battery. Also, if you just directly let the 12v come through somehow, they don't want a situation where there is excessive drain, destroying the LION battery.

Yes you could theoretically account for all these things and build in some sort of protection, but why? Its an edge case, and its called out clearly in the manual. I think all the electric vehicles on the market work this way right now.
 
Was something left on? Why would the 12v battery drain down in three weeks? You might need a repair for a key off draw.
 
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