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12v battery problem and stranded!

qwk

P130DL
Dec 19, 2008
3,024
857
>I want to say a group 75 battery [Smop]

The U-1 (form factor) battery I listed is reversed, ie POS on lf NEG on rf. MS batt has NEG at left rear & POS at right front thus is a custom battery as there is NO such industry group for this configuration. This from Battery Systems. Also the posts might be a different shape. Hard to tell peering into the limited space above POS terminal with that rat's nest of wires all connecting to the POS post. U1R batt has terms reversed but both in front and is only available NON-AGM.

Bottom Line: Might be best to stick with Tesla keeping your 12v battery up to date & warranted, since the OEM battery is not available and since replacing it is a genuine nightmare. If you install remote terminals inside the Frunk then you can quickly connect a U1 battery into the 12 volt system which is equal or better than the latest Tesla batteries. Or any other 12v battery.


>And how do you pop the trunk with failed 12V? [MK]

@islandbayy: The video you reposted does not answer this question assuming 'trunk' to mean HATCH.

Ok, I levered off the plastic cover and my MS does have the manual release cable to open Hatch. Pry yours off a few times to make it easier to do. This in a car with NO 3rd seats. Problem solved, thanx!
--
Here is a pic of the C&D battery that Tesla currently uses.
 

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qwk

P130DL
Dec 19, 2008
3,024
857
Hmmm, I was told multiple times that the MS monitors each cell of the battery and had a non-standard connection. I was working on a Lithium replacement for the MS Battery, but scrapped the idea after being told here and by a service tech of the odd connection. I guess I am going to go at it again!
Tesla monitors the traction battery closely, but the 12V just has a voltage reading that they go by.
 
I got my car about three weeks ago. Today at work trying to drive home I got three error messages. That the car needs service, may not restart and has a low 12V battery. All was functioning, climate worked, lights worked, power lift gate worked but car would not come out of P. After 15 min with Tesla on the phone and Tesla about to send a service guy all over sudden I could put the car in reverse and it came to life. I kept getting a few more error messages but could drive it to the service center. I now have a loaner until they figure out what is going on. Does that mean I may have the same battery issue that everybody here has been talking about? They should know by now what's wrong right?
What do you think I will need, just a new red battery or a new DC DC converter? I am bit confused and surprised to have this issue in a three week old car.
 

JRP3

Hyperactive Member
Aug 20, 2007
23,931
67,202
Central New York
I think Tesla has a problem with their DC/DC converters. It's an area that some of us have struggled with in our DIY conversions. I'd be surprised if Tesla wasn't aware of the following possible issue: The converters have capacitors in them that get charged to pack voltage. When you accelerate hard the pack voltage will drop, and the caps, at higher voltage, will drain back into the pack, unless an inductor and/or diode is in place to block it. Essentially the caps are trying to power the car for a split second, and doing this repeatedly can damage them. At least that's the theory.
 
Got my car back today. Didn't really tell me what's wrong with the car, but they replaced 2 coolant pump and replaced my 12V battery. A lot of times I think Tesla just tell you the simplify version of what went wrong, but really there is more that went wrong then written up.
 

wycolo

Active Member
May 16, 2012
3,120
484
WA & WY
> they replaced 2 coolant pump and replaced my 12V battery. [simplesolar]

The pumps were the problem and they gave you the new 'red' battery *as a precaution*. I think we should wait for results before investing effort into doing replacements for the red battery. Now Tesla will still be replacing the red ones if they ever get cycled down just as a precaution, but that shouldn't count as a failure/replacement.

Getting a 12 v voltmeter ON THE DASH where you can easily see it should be a priority, and is on my list of things to do.
--
 
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Cottonwood

Roadster#433, Model S#S37
Feb 27, 2009
5,089
182
Colorado
<C&D Deep Cycle Battery> is the web page on these batteries, and here is the spec sheet on them: http://www.cdtechno.com/pdf/lit/12_1061_0412.pdf

Seems to be a quality choice. Any problems with batteries of this quality are probably in the charging and management, not the batteries. Has anyone had trouble with these C&D, "red" batteries?

The battery I removed was a grayish made in Taiwan battery. Would be interesting to know how long they have been using these C&D batteries for.
 

dsm363

Roadster + Sig Model S
Moderator
May 17, 2009
18,280
162
Nevada
The battery I removed was a grayish made in Taiwan battery. Would be interesting to know how long they have been using these C&D batteries for.

I think since the summer sometime. They've only been replacing ones that have caused problems or sent out error messages. I believe all new cars have the red battery but am not certain about all of this.
 
I got my car back today. In addition to replacing the 12V battery they replaced the "junction box" after noting the following:

Noted High Voltage Interlock errors. Found HVIL too high at 5.2 volts. Removed &Reinstalled back seat bottom to check for HVIL issues. Found high resistance at 168ohms in Master charger circuit. Narrowed problem to faulty lid switch in high voltagejunction box. Replaced high voltage junction box and rechecked resistance. Found to beok at 61 ohms. Update TDS case and car was released by engineering.





Hope this fixed the problem.
 
I got my car back today. In addition to replacing the 12V battery they replaced the "junction box" after noting the following:

Noted High Voltage Interlock errors. Found HVIL too high at 5.2 volts. Removed &Reinstalled back seat bottom to check for HVIL issues. Found high resistance at 168ohms in Master charger circuit. Narrowed problem to faulty lid switch in high voltagejunction box. Replaced high voltage junction box and rechecked resistance. Found to beok at 61 ohms. Update TDS case and car was released by engineering.





Hope this fixed the problem.

Interesting--'car released by engineering'. It certainly sounds like they know about the issue and how to resolve it--I hope.

Glad you have it back.
 
Interesting--'car released by engineering'. It certainly sounds like they know about the issue and how to resolve it--I hope.

Glad you have it back.

Yes I hope so too.
I am also very happy to be back in my own car. The loaner (performance model as usual) was quite new and nice. However, there is nothing like my own car. It fits better, rides better and feels better, somehow.
 
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JRP3

Hyperactive Member
Aug 20, 2007
23,931
67,202
Central New York
I'd be more tempted to carry a small 12V booster pack, you don't really need that much current a jump from another car would provide, and you have a way to jump yourself if no one else is around. You could get one that's an air compressor as well in case you get a slow leak in a tire.
 

Bobfitz1

Active Member
Supporting Member
Sep 24, 2012
1,236
4,009
Ludlow, Vt
Have not been following the long, long 12V battery saga closely. Does anyone follow why TM let's this bleeding sore go on and on unfixed, instead of switching to a 12V Li Ion battery? They've increased avg prices by thousands this year, so can't claim it's too expensive to get it fixed once and for all.
 
This happened outside Spago in Beverly Hills at a party.
Now it happened again after 6 week trip and the car plugged in.
Tesla monitored from the satellite and Sid its the 12 volt again.
very
frustrating

Yeah I'd say that's frustrating. I'd make sure they check cables, etc along with battery replacement. Might be something else than battery alone. Let us know what they say. Sorry you're having this issue.
 

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