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Which cooling louvers open during supercharging?

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sorka

Well-Known Member
Feb 28, 2015
11,684
9,660
Merced, CA
Charging at reduced rate with battery at 115F currently. The cooling system is screaming but muted because both inlet louvers are closed. As I recall, when I was paying attention to these when I first got the car one of them would open up all the way once full cooling kicked in.


Am I missing something here or
 
Been studying the schematic from the link. Pretty sure you are correct Mike.

attachment-php-attachmentid-20088-d-1365905905-png.132095


The schematic is pretty clear. The rotor, charger, and inverter coolant doesn't even mix with the battery coolant and passes only through the center radiator.

Both of the side radiators service HVAC and battery cooling.
 
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Finding images of the thermal diagnostic screen in different states helps clarify things a bit:
KijMR0n.jpg


So the glycerin based battery coolant is shared by the charger, rotor, dc-dc converter, and inverter, but depending on how the valves are opened determines which systems receive passive cooling vs active cooling.

The radiator in the center is for passive cooling and only passes glycerin based coolant through it.

The AC condensers on the sides are where compressed warm refrigerant passes through and is where the active cooling system expels hot air from running over the condensers.

Within the target range of passive cooling, the battery coolant will pass only through the radiator. When the active cooling target is reached, the coolant for the battery will be isolated from the drive/inverter/charger/etc systems and will pass through the chiller.

The active target cooling temperature changes based on whether your super charging or not, whether you have max battery turned on, and probably a dozen other factors.

So the short of it is, the center radiator is not part of the active cooling system for the battery.
 
Charging at reduced rate with battery at 115F currently. The cooling system is screaming but muted because both inlet louvers are closed. As I recall, when I was paying attention to these when I first got the car one of them would open up all the way once full cooling kicked in.

I saw someone mention recently that at their annual inspection Tesla noticed that the louvers weren't opening and replaced them with a new version. So apparently they can fail in a way that doesn't set an error code. You should probably contact your service center and see what they say.
 
I saw someone mention recently that at their annual inspection Tesla noticed that the louvers weren't opening and replaced them with a new version. So apparently they can fail in a way that doesn't set an error code. You should probably contact your service center and see what they say.

My appointment is Monday morning in Dublin. I plan to mention this first thing along with the other data I've been collecting. I've also been forwarding all it directly to the service manager in Fremont since I started with them first but they declined being able to diagnose the issue without access to a full charge rate supercharger.

I suspect if they'd done a thermal diagnostic they would have already found the issue without me needing to run to low SOC and charger at at full rate SC.
 
@sorka my understanding of the thermal management system matches yours: when in series mode the HVAC system provides cooling for the battery loop, and this is often in high gear for supercharging sessions.

I can't ever recall the louvers not being open when I've had the system kick high, but I'll admit to not specifically checking every time it's happened.

I think your plan of action in case of a fault is a good one...
 
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I saw someone mention recently that at their annual inspection Tesla noticed that the louvers weren't opening and replaced them with a new version. So apparently they can fail in a way that doesn't set an error code. You should probably contact your service center and see what they say.
That was me, and the service record said "during pre-appointment diagnosis tech found radiator louver alert present". So it was actually found remotely, not from visual inspection. They told me about it when I dropped off the car. The service record also said "pulled logs and checked for faults. No active faults found." So it seems an alert is different from a fault?
 
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My appointment is Monday morning in Dublin. I plan to mention this first thing along with the other data I've been collecting. I've also been forwarding all it directly to the service manager in Fremont since I started with them first but they declined being able to diagnose the issue without access to a full charge rate supercharger.

I suspect if they'd done a thermal diagnostic they would have already found the issue without me needing to run to low SOC and charger at at full rate SC.

Curious what did they end up doing and if it improved the charging rate?