How do clear "replace 12v battery" warning?

[efusco]

For background, see this thread: Blackvue 750 causing 12V battery warning?

Obviously, the easiest way would be to replace the 12v battery, but if you read the thread above you'll see why I'm skeptical that the 12v actually needs replacing. So I'd like to be able to experiment and see if unplugging the Blackvue will prevent the warning from coming back on.

I did a hard reboot of both the center display and the dash display, but that did not clear the warning.

Does anyone know how to clear that?

 

[Exiom]

AFAIK once the warning appears... you need Tesla to reset that code... whether you replaced the battery or not

or their software to reset that code... if you can get your hands on it... I think some states in the US can for a fee?

 

[efusco]

AFAIK once the warning appears... you need Tesla to reset that code... whether you replaced the battery or not

or their software to reset that code... if you can get your hands on it... I think some states in the US can for a fee?

Thanks, was afraid of that.

 

[apacheguy]

It is either a DTC (which Tesla will need to reset) or an alert which can often be cleared by rebooting the gateway.

 

[efusco]

It is either a DTC (which Tesla will need to reset) or an alert which can often be cleared by rebooting the gateway.

Not sure what "the gateway" is, but I did reboot the center and dash displays and it did not clear.

 

[apacheguy]

Not sure what "the gateway" is, but I did reboot the center and dash displays and it did not clear.

GW is an RTOS computer mounted on the MCU and it provides the CAN link “firewall” between the Ubuntu systems and the embedded controllers.

 

[apacheguy]

Hacking a Tesla Model S: What we found and what we learned

 

[Terra117]

I got the warning. The battery was fine. It was caused by my car being in a sleep state for a long time. Since the battery wasn't being charged, the voltage dropped below some threshold. Once that happens you need to have the service center do the reset.

They advised me that when I'm away from home for long periods of time I should periodically wake the car up by turning on the climate control. Now when I'm away, I turn on the climate control at least once a week. Everything's been fine ever since.

 

[efusco]

I got the warning. The battery was fine. It was caused by my car being in a sleep state for a long time. Since the battery wasn't being charged, the voltage dropped below some threshold. Once that happens you need to have the service center do the reset.

They advised me that when I'm away from home for long periods of time I should periodically wake the car up by turning on the climate control. Now when I'm away, I turn on the climate control at least once a week. Everything's been fine ever since.

I suspect that's what's going on here. It's just been 13 months since it was replaced, but my service advisor says it needs to be replaced...no warranty, but he's gonna try to keep the cost down for me. Frustrating b/c I suspect the battery is fine.

 

[Tripple_T]

The warning will clear when the battery is replaced. There is not a code that needs to be reset. In my experience the system is looking at the voltage of the battery on a few cycles and sees when the voltage comes up. That is my best guess to how it is fixed.

 

[efusco]

The warning will clear when the battery is replaced. There is not a code that needs to be reset. In my experience the system is looking at the voltage of the battery on a few cycles and sees when the voltage comes up. That is my best guess to how it is fixed.

It isn't so much the act of replacing the battery that clears the code, it's the disconnection of the HV connector that completely shuts down the car. Learned this just yesterday. If you simply disconnect the 12v and reconnect it will not clear the code.

 

[apacheguy]

It isn't so much the act of replacing the battery that clears the code, it's the disconnection of the HV connector that completely shuts down the car. Learned this just yesterday. If you simply disconnect the 12v and reconnect it will not clear the code.

Well, if you disconnect the 12 V supply, the contactors will open, disconnecting the HV pack. Is that what you mean?

 

[efusco]

Well, if you disconnect the 12 V supply, the contactors will open, disconnecting the HV pack. Is that what you mean?

Well, that's not what the tech showed me...but I see what you mean, it seems that would do the same thing.

 

[Exiom]

Because it has been reported by others that, changing their own 12V battery does not clear the warning so thus...

Well, if you disconnect the 12 V supply, the contactors will open, disconnecting the HV pack.

This doesnt work? Because to replace it you have to disconnect it.

Well, that's not what the tech showed me...but I see what you mean, it seems that would do the same thing.

So would disconnecting the First Responder Loop achieve the goal? Would you please kindly share some more info? so those of us who wants to replace our own battery can do so

 

[efusco]

Because it has been reported by others that, changing their own 12V battery does not clear the warning so thus...

This doesnt work? Because to replace it you have to disconnect it.


So would disconnecting the First Responder Loop achieve the goal? Would you please kindly share some more info? so those of us who wants to replace our own battery can do so

Yes, it was the first responder loop that he showed me.

 

[msaficionado]

If you pull the first responder loop and 12v power, the alert should go away. I heard this is hard on the contactors, though.

 

[apacheguy]

If you pull the first responder loop and 12v power, the alert should go away. I heard this is hard on the contactors, though.

You can wait until the contactors open by going to power off vehicle on the CID and then pulling the 12V.

 

[AWDtsla]

You can wait until the contactors open by going to power off vehicle on the CID and then pulling the 12V.

If disabling the 12V opens the contactors, what else could opening the first responder loop do? The car is already without any power.

 

[apacheguy]

If disabling the 12V opens the contactors, what else could opening the first responder loop do? The car is already without any power.

Correct. There is no point to disconnecting the first responder loop if 12V is disconnected. However, the service manual definitely recommends it.

 

[JCBX]

I have been driving for 3-4 month now with the 12V service needed alarm on

today I disconnected the "frl" alone .... and that didnt do it ...

then I did disconnect the "frl" again and the negative on the 12V battery

I measured 12.75V on the battery disconnected

put all back again and the alarm was reset

time will tell if it last