12v battery issue explanation, sort of...

[wycolo]

No need to remove nose cone to charge MS battery. Just remove the panel above. The one with the two chrome 'step pads'. All the white plastic connectors are 'pull out' posts so pry straight up and they will not be damaged. Easier if you remove fuse/wiper panel first, then the two side covers. The side covers each have a 2in dia soft rubber bolt head that you just unscrew with your fingers (see it sitting on shelf).

Best thing is that this process does not affect the exterior of the car at all.
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Factory omitted the center white pin on my car. Before replacing panel I'll move it to far right position (just to be symmetrical).
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[montgom626]

And because he had to come to my home to swap mine out, I got to see the process.

Where is the 12 volt?

 

[wycolo]

> Where is the 12 volt? [montgom626]

Remove the top panel (wipers/fuse boxen) from above frunk. Look under the 2 inch dia alum tubing strut on passenger side and there it is. You can only see the black negative terminal easily. Strut probably has to be unbolted to remove batt (or more stuff even).
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[JRP3]

No need to remove nose cone to charge MS battery. Just remove the panel above.
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Is that faster than popping off the nose cone? Because it looks more complicated.

 

[techmaven]

I am curious if one can plug in one of those small solar 12v chargers into the cigarette lighter to help maintain the 12v battery. Or if it is possible to use one to engage the traction battery if the 12v battery is dead.

 

[wycolo]

> Is that faster than popping off the nose cone? Because it looks more complicated. [JRP]

Faster is not the issue really, since once you remove the front top panel you are certainly going to bring out contacts of some sort for instant connection to 12v battery forevermore. This cannot be done by just removing nose cone. New outlet probably will be installed on threshold panel.

Re: 'Popping off the Nose Cone'. Easy for you to say until you try to do it. When I needed to charge battery (it was @12.1 volts ie entering the Danger Zone!) you don't have time to carefully fuss with exterior trim that can be permanently damaged. You want to work from the inside. Turns out to be a piece of cake since you are working with those white plastic pull posts. Cheap at any auto parts store if you lose or damage. Besides my nose cone was encrusted with bugs and was not yielding at all to credit card persuasion.

There are two black 'center pull' posts on either end of the threshold center panel. With this type of post you pry out the center using a screw driver. See on shelf next to 2 inch headed bolt. Forgot to mention these two.
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[Doug_G]

Re: 'Popping off the Nose Cone'. Easy for you to say until you try to do it.

For me, easy to say after trying to do it. All it takes is a credit card you don't care much about, and a bit of prying. No biggie.

 

[islandbayy]

I am curious if one can plug in one of those small solar 12v chargers into the cigarette lighter to help maintain the 12v battery. Or if it is possible to use one to engage the traction battery if the 12v battery is dead.

No, car disables the 12v outlet in the cabin after the vehicle has been exited.

 

[Evpro2]

To have this 85kwhr car disabled by a 12V accessory battery is tragic. A small dedicated solar panel? The least they could do is make jump charging and battery replacement a snap.

 

[wycolo]

Trailered my dead MS to service yesterday. I kept 12v battery on slow charge for 5 days so 400v battery would hopefully not be depleted but remain at '240 miles' with minimum daily loss.

First thing Service did was replace 12v battery with latest issue 'partial deep-cycle' 12v battery. So Factory now realises the importance of deep-cycle capabilities, albeit partial. My old, perfectly good. 12v battery was made in Vietnam(!) and was AGM sealed, as all MS batteries have been.

Dead car due to complications from attempted s/w update install outside of 3G coverage zone (will report later).
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[wycolo]

Service found 240 miles remaining in 400v battery, so keeping 12v battery charged up didn't hurt. Car is dead-dead with NO drain off 400v battery during the 5 days. No vampire losses, no losses at all.

All engineering teams are involved with this one. That's all we know at this point.
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[stevezzzz]

For me, easy to say after trying to do it. All it takes is a credit card you don't care much about, and a bit of prying. No biggie.

Doug, what about for those of us with the early, two piece nose cone? I like wycolo's approach on its face, because it only requires removing interior panels where cosmetic damage isn't as much of an issue.

 

[Al Sherman]

Trailered my dead MS to service yesterday. I kept 12v battery on slow charge for 5 days so 400v battery would hopefully not be depleted but remain at '240 miles' with minimum daily loss.

First thing Service did was replace 12v battery with latest issue 'partial deep-cycle' 12v battery. So Factory now realises the importance of deep-cycle capabilities, albeit partial. My old, perfectly good. 12v battery was made in Vietnam(!) and was AGM sealed, as all MS batteries have been.

Dead car due to complications from attempted s/w update install outside of 3G coverage zone (will report later).
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This sounds exactly what I had when I attempted to install 4.4. A bad 12 volt depleted by the install process. The issue was the 12 volt not sustaining during the install. The complications came because the car went dead during the install. The Service Center took a couple of days to get it up and running as far as the complete firmware package but the bad 12 volt was the only real issue.

 

[wycolo]

Al, yes you are the Poster Child for this scenario, and I had that very much in mind. When I arrived home late, I plugged in as usual. The next morning the screen showed 241 miles just as I expected, but after a few seconds the screen changed to: 'car awakening' followed by black screens. Voltage was 12.1 on the meter. Now 12.1 is not 12.6 nominal value, but is that sufficient drop to trigger a shutdown??

The following day it was on trickle charge, but the following night charger was NOT connected. Next morning back to 12.1v so I decided to charge at all times, except when I was actually moving car around, first onto tow dolly and finally onto trailer.

After 5 days battery measured 240 miles according to Denver Service. Vewwy intewesting.
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[montgom626]

12 volt on a trickle charger prevents the daily vampire loss ????

Service found 240 miles remaining in 400v battery, so keeping 12v battery charged up didn't hurt. Car is dead-dead with NO drain off 400v battery during the 5 days. No vampire losses, no losses at all.
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So you are suggesting that simply putting the 12 volt on a trickle charger prevents the daily vampire loss of 2-3 kW per day???? I think you are onto something here! I look forward to your next report. A trickle charger should use much less the 2-3 kW per day vampire loss from the main battery. Right?

- - - Updated - - -

The following day it was on trickle charge, but the following night charger was NOT connected. Next morning back to 12.1v so I decided to charge at all times, except when I was actually moving car around, first onto tow dolly and finally onto trailer.
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Why do you move your car on a tow dolly? And then a trailer?

 

[Al Sherman]

Why do you move your car on a tow dolly? And then a trailer?

When the 12 volt dies the eBrake engages and the car is not moveable. Dollies are the only safe answer. The 12 volt failing during an installation complicates things further. I'm guessing the Service Center wanted the car to make certain it was just a bad 12 volt and not something more serious/complicated. The Rangers DO have the ability to put in a new 12 volt and force an upgrade over WiFi but it is very time consuming, and requires special "secret" access codes that not every Ranger has. Though this is possible with the Ranger that has the access codes, it doesn't rule out other possible problems that would create the same symptoms hence they probably want the car to be certain/thorough.

 

[wycolo]

A week ago 8am the 2 screens were operational for a few seconds reporting 241 miles standard charge, car having been plugged in at midnight when I got home. Then both screens died and speedo screen showed "car awakening" black & white banner which only lasted for a couple seconds. Dead screens & silent car - no pump, no cooling fan behind the 17in screen, nada, nichts.

Rebooting screens did not work except booting buttons above the 2 wheels did create on the speedo screen a big T and panoply of sensor icons, just for few seconds. Blinkers, door handles & windows did work. So decided to hook up charger to 12v battery immediately since voltage was 12.1v, the lowest I've ever seen (first time ever below 12.6v).

Rear axle was locked solid so had to drag car out into the open using chains on the front A arms. Don't have any mini-tow dollies the kind that carry dead wheels using 4 rubber wheels of their own. So had to drag MS across the dry road base surface. Not too stressful on the tires compared to dragging across pavement.

I first put car up on a full-size tow dolly (made for pickups & big suvs) thinking that could get me the 250 miles to Denver Service. Simple job using an 8ft 6x6 and 2 floor jacks. But the lower lip in front was riding a bit low to the pavement so I would have to remain on the roads, no stops for fuel, etc. Anyway, nice to know the MS fits on the tow dolly. Now to get it up on the 18ft flatbed trailer.

Using a Bobcat Telehandler forklift with an 8ft extension on one of the forks allowed lifting the front end of the MS so the trailer could be backed under it. Next lifting the MS rear the same way allowed backing the trailer under the rear axle and into final position. Connected a deep-cycle 12v battery in parallel to keep the internal 12v battery up to spec during the long trip.

Diagnosis is bad contactor(s). Nothing to do with attempted S/W upgrade the night before. Just a coincidence. Replacing traction battery unit as a precaution due to persistent 'contactor faults'. Luckily they had one available. That is all I know at this point. Car has about 8k miles.

So this is NOT a 12 volt battery problem but a RELAY (contactor) FAILURE. Still, it required keeping the 12v battery charged up so as not to jeopardize the health of the traction battery. Any DEAD CAR situation requires immediate 12v battery FIRST AID. It is the least we can do.
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[montgom626]

When the 12 volt dies the eBrake engages and the car is not moveable. Dollies are the only safe answer. .

What kind of dollies? Brand name?

 

[Al Sherman]

What kind of dollies? Brand name?

No idea here. But, the first tow truck driver didn't even own a set. The second guy didn't bring them. I'm assuming Tesla has worked this out a little since then.

 

[PatP]

No idea here. But, the first tow truck driver didn't even own a set. The second guy didn't bring them. I'm assuming Tesla has worked this out a little since then.

Exactly the same problem I had at about 5000 miles. However, I don't understand why they didn't boost your 12v to put the car in neutral. It's really tricky to do though:

While 12v battery is being jumpstarted, you put the car in neutral from the car setting menu and, very important, you then quickly turn it off from the same menu. If you don't do this, car will put the parking brake back. Really weird.