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Main battery voltage too low, will not charge

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Moderation comment - thread moved from UK and Ireland sub forum for greater visibility

I bought this Tesla Model S 85 few months back. Was scraped on the left hand side, no airbags deployed, no error messages.

I drove it home and charged fine. Took it at the end of September to a body shop for repair. They were quite busy and the car sat for ages. About 10 days ago they called and said they need to move the car but shows 0 miles and will not drive.

I ordered a 3 pin plug charger and went there. Started to charge fine. Probably they only left it for few miles range. Called me again days later that it shows again 0 miles, and will not start. The charge port will not open. We had a fully charge 12v battery connected to the car. Opened manually the charge port, also had to unlock it manually from inside the trunk, plugged in the charger, says starting to charge, but few seconds after said charging complete, but still 0 miles. Took it home on a recovery truck
Tried with my home wall charger but same results.
I'm guessing the main battery voltage is too low. How do I put some volts in?
 

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The 12V battery is probably dead again, unless you have a new replacement. Lead Acids really don't like to be discharged.

Leave it plugged in, it may slowly recharge the pack and start working after a day or so - or maybe it is shut off for safety. Look in the main forum under battery, this is not a UK specific problem.
 
Complete guess here, but is it possible if the battery pack is totally empty there is not enough power to engage the main breaker (assuming that the system that engages it cant be powered from the 12v/charge port connection)

There's a video on Youtube of James May who had this issue for similar reasons with his Model S... he made an addition to help deal with any future instance ... but I'm sure OP and he will manage to avoid that now that you know!
 
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Looked a lot online and couldn't find anything. Send same message to Electrified Garage USA, just got this response, see screenshot attached.
12v 110amp battery is on charge overnight and I have 120amps boost charger. Will give it a try tomorrow. Fingers crossed
 

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Good to know. Tangentially, I saw that the newest cars have a lithium '12V' pack, and these have a surprisingly large supply current capability in relation to their charge capacity. (I think stepped up from 3 cells). I expect the monitoring circuits will want to see that the 12V rail holds up under heavy load since the sign of any battery being tired is that the internal resistance increases (off load voltage looks OK, on load is poor).
 
I have the same problem on my 2014 model s . Currently dropped the main battery pack and remove the pyro fuse and I’m getting 93 dc volts from the fuse terminals.Assuming that the pack is split in half once the fuse is removed . I’m way under voltage. My battery is a 350 dc volts . I need to be around 175 volts fully charged in the pyro fuse terminals. Does anyone try to charge from the pyro fuse terminals to kick start the battery and have the system recognize it ? I don’t want to open the whole battery cover to charge every brick back.
 

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When connected to the charger, is the clicking taking a while or weak sounding?
It doesn’t do any clicking. I have to pry the door open and the ring is red. But then when I press the wall charger button it releases the charger but it doesn’t activate the latch down to reinserted back in . I had to use a card to push down and insert the charger back in .
 
Can you measure the voltage from the cigarette lighter? The 12V plug... you might have too little power in the low voltage circuit to close the contactors in the pack. I had an HVIL Fault from the rear motor that drained the battery and eventually killed two 12V batteries within a few months. I remember everything was as if it was in slow motion. Took over a minute to power up the car once I opened the doors.
You might could try jumping the 12V from the nosecone. If the low voltage circuit has no juice and the DC-Dc converter isn’t charging it because the HV pack is dead, you can’t charge the battery.
 
The main contactor will not close if the 12v battery is low. Replacing the 12v battery is a good start, after that just plug it in and wait, it might take anywhere between 4 to 6 hrs for the HV pack to start getting any charge.
If that doesn't work, you might need to get the main battery pack repaired. I have seen that Charge Complete at zero miles notification before, and it meant that there was a fault that needed to be corrected in the main battery (or Tesla would replace the main battery with a refurbished or new one). These companies can help too:

www.057tech.com
www.recell-ev.com
 
I have the same problem on my 2014 model s . Currently dropped the main battery pack and remove the pyro fuse and I’m getting 93 dc volts from the fuse terminals.Assuming that the pack is split in half once the fuse is removed . I’m way under voltage. My battery is a 350 dc volts . I need to be around 175 volts fully charged in the pyro fuse terminals. Does anyone try to charge from the pyro fuse terminals to kick start the battery and have the system recognize it ? I don’t want to open the whole battery cover to charge every brick back.
The reason u get voltage at pyro is cause pack is connected to BMS but i'm pretty sure u can burn the bms trying to charge from there
Also, fuse is in between 14th n 15th module, not half the pack...
On newer packs there's a connector that goes from HV to outside (my guess for discharging packs when contactors don't close) that could possibly be used to charge but not sure its there for older ones...
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