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J1.2 - "12 Volt battery low" message

prj

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That's a good point. But, if his Taycan is giving a 12v battery low message, isn't that a sign that something (perhaps the auto 'tops it up' feature) may not be working properly?
It's a sign that either the DC/DC is failing or the 12V is failing (unless there are other faults present in the car which do not allow the engagement of the HVB contactor). Whether he has accessories is irrelevant in either case.

My point is, something is damaged, and accessories or trickle chargers aren't going to make any difference. If everything was working correctly this would never occur, and if it's not then the car will be undriveable soon regardless if it has any accessories or not. It's like focusing on water in a puddle when there's a tsunami coming.

Kinda sucks that J1.2 is affected though :/
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Has a Porsche fitted dashcam.
Had the car for 9 months and the camera has been fitted all that time.
The car is run pretty much every day.
Only had a electrical niggles for a few days

Assist has just left.
Had no idea what the issue is.
When it's in drive, it behaves, when it's stopped it misbehaves.
Now it won't take AC charge.
LV battery is fully charged.
And his scanner wouldn't connect to the car.

He's booked it it with a dealer tomorrow who isn't too far out of the way and a courtesy has been ordered.
Hopefully, I'll pick up on Thur night / Fri once they had chance to scan it properly.
Just hope it's not with them for any longer.
 

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Now it won't take AC charge.
That's the culprit then, no AC charge, so it can't connect the HVB contactor on demand, that also stops the 12V from charging. Might be intermittent.
 
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ct4s

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Sat in the dealership.
They can’t run diagnostics until Monday.
Courtesy car on its way from Enterprise - expecting a 1.0 Polo.
It drove fine to get here. When i stop it’s not fine.
It’s happily charging on the dealers DC charger, and when I arrived the LV Battery error had gone.
But interior light, comfort access etc still not working.

I’d be better off in this [rather awesome] child’s car :)

Porsche Taycan J1.2 - "12 Volt battery low" message IMG_6827
 


Dee

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It should be standard that the voltage of the 12V battery is shown in the right dial of the instrument cluster.
That way you can monitor if the 12V battery is charged/charging or not:

13.4V: battery is charged, all good.
<13.0V: battery isn't charging, not good!
~14.4V: battery is charging by the DC/DC charger.

Every sales person should point customers to that option in the dial.
I don't get it why they don't know or don't tell.
It's the easiest way to actually see the status of the 12V battery circuit.
 
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ct4s

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Initial testing suggests the HV and LV battery are fine.
Likely to be a BMS and / or software issue.
Hoping a firmware reset / update on Mon will fix it.
 


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ct4s

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PS I didn't know they made a convertible version of the 917.....🤪

IMG_6827~2.webp
It's a lucky child who gets this for Christmas
 
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Got it back last night.
All being well, it was a software glitch.
Modules - can’t recall if he said 26 or 28 - had their firmware updated / reset.
80 miles later, no issues so far.
Hopefully that’s it.

PITA to have an issue. But Porsche Wolverhampton were great.
It wasn’t booked in when I left it with them last Thursday, but they managed to work on it Monday afternoon and most of Tue. Which is as much as you could expect.
They had no courtesy cars due to last minute visit, but Enterprise supplied one to the dealership which was covered by the Porsche Warranty. (C-Class, quite nasty, put me completely off Mercedes.)

Fingers crossed this was a one-off.
 

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Teething pains of the first year production of a new model (J1.2). I hear from service people Macan EVs are experiencing much more of those.
 

exilen94

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Does turning car on and then off trigger car to charge 12V battery? Or should I leave the car on for minimum 10 minutes without driving?
 
 








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