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The "Emergency SRS Disable" switch

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TEG

Teslafanatic
Moderator
Aug 20, 2006
22,101
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Martin had posted this photo:
roadster-delivery-031small.jpg


Some people asked what it does exactly.

Reportedly it disables everything electrical including disconnecting the high voltage battery pack and all the air bags triggers. It is meant to be used by emergency crews (such as the fire department) if a Roadster is in an accident and they need to cut things to get someone out.
 
Questions, Questions, Questions....

First of all, where did Marting post this picture?

Second, it appears this is next to the controller (PEM as Tesla says). If so, why are there the numbers 185 where the controller is? That is the KW output of the battery pack. Ever since when did Tesla start doing this? Are they gonna name their models based on the KW output? (not a bad idea)

Third, this is not the same switch that automatically disconnects the battery pack in case of an accident, right? Then that would mean that this yellow switch is redundant.

A picture is worth one thousand words!
 
Questions, Questions, Questions....

First of all, where did Martin post this picture?

Here...

Second, it appears this is next to the controller (PEM as Tesla says). If so, why are there the numbers 185 where the controller is? That is the KW output of the battery pack.
I think it has said "PEM 185" on there for quite a while now.
185kW=248hp=Powertrain1.0 output.

I wonder what the Powertrain 1.5 PEM will say on top?

Third, this is not the same switch that automatically disconnects the battery pack in case of an accident, right?

I think there may be some automatic disconnect that disconnects the pack when triggered by an accident. The yellow SRS tab may not actually be a switch, but rather covers a wire that can be cut when emergency crew want to make completely sure that all power is off. In other words the power ~may~ have shut itself off, but this provides a way to be absolutely sure.

In any case, I don't think it is anything owners need to be concerned with. It is there for emergency personnel who should know what it means.
 
SRS = Supplemental Restraint System

in this case it does mean the combination of airbags and belt pretensioner.

one very critical situation in case of an accident is that the airbag might not be deployed.
But when the system (sensors, etc.) is still "alive", it is an extreme danger for the rescue team when the get "in" the car, to give first aid to the driver / passenger.
If the aribag deploys in this situation (very likely possible at a damaged car) - it blows up with speeds of about 200km/h, this is extreme (life)-critical to a person only a few centimeters away from the deploying airbag - e.g. someone bending inside the car to see for the injured.

So this SRS switch should prevent the airbag from deploying and release /prevent to work for the belt pretensioner. - should be equivalent to disconnecting the plus-cable from the car battery, but only on the SRS/airbag/belt pretensioner issue, on an older ICE.

my thoughts.
 
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Does anyone know, what systems are shut down, when someone cuts the cable? What about batterie cooling or heating, will the displays go dark, when the cable was cut? I am thinking of buying a salvage roadster and want to figure out, if the batterie is still good.

Thanks,
Marco
 
Does anyone know, what systems are shut down, when someone cuts the cable? What about batterie cooling or heating, will the displays go dark, when the cable was cut? I am thinking of buying a salvage roadster and want to figure out, if the batterie is still good.

Although this video is for the Model S, I would think the same systems would be disabled.
 
Thanks for your answer. So by cutting the wire, a 12V circuit will be interrupted and a relay can't operate anymore. Does anyone know, what systems are controlled by this relays or does anyone have a schematic of the power circuit from the Roadster?