Insider gems part two: Inner workings of Tesla's Model 3 [Videos]

The powertrain is far from the only innovative feature of Tesla’s Model 3. As the first units make their way to customers, aficionados are piecing together the details of the new EV’s novel heating/cooling system, keyless entry system and more. 


Above: Tesla's Model 3 (Image: Tesla)

Model 3 has a strikingly minimalist interior, and one big part of that is the HVAC system, which presents only two long slits in the dash, in place of the usual clutter of vents and controls. Tesla’s patent application reveals some of the technical details of how it works, and Trevor of the Tesla Model 3 Owners Club gleaned a few more tidbits from a Tesla engineer at the launch event (as reported by CleanTechnica and Electrek).


Above: Where are the vents? A look at the sleek Model 3 HVAC interior design (Source: Electrek)

The system uses a single blower, which directs air through two parallel linear vents (plenums in HVAC jargon) that emit two intersecting planes of air. By varying the amount of air coming out of the smaller vent, the vertical direction of the airflow can be controlled. Tiny vanes concealed inside the larger plenum control the side-to-side direction of the air. A third hidden plenum blows air on the windshield for defrosting.


Above: Tesla's patent schematic displays what goes into the Model 3 HVAC system (Source: Electrek)

This ingenious system allows the direction of airflow to be very finely tuned, reduces the mechanical complexity of the HVAC system, and allows Model 3’s dash to be not only less cluttered, but considerably smaller than the ones in legacy vehicles.


Above: Trevor Page breaks down how the Model 3's unique HVAC system works (Youtube: Model 3 Owners Club)

Tesla has also done away with the traditional key fob, or at least shrunk it to the size of a credit card. As the user manual (via Electrek) explains, the key card uses a fairly new form of RFID technology called near-field communication (NFC), the same system that enables tap-to-pay transactions at retailers. To unlock the car, you tap the card against the B-pillar. However, the preferred way to gain access to Model 3 is by using an authenticated smartphone. The card is intended to be used for valet parking, or as a backup in case your smartphone gets lost or runs out of power (Tesla recommends keeping both your phone and key card with you).


Above: A look at using Tesla's Model 3 key card at the B-pillar for entry (Source: Electrek)

The Model 3 mobile app communicates with the car using a newer form of Bluetooth called Bluetooth Low Energy (LE), which is built into most current smartphones, as Car and Driver explains. Bluetooth LE allows for a low-power, always-on connection between phone and car, so when you approach the vehicle with your phone, it automatically unlocks the doors and adjusts the seats and other features to your preferences. When you walk away, the doors automatically lock (assuming you have the Walk Up Unlock and Walk Away Lock features enabled).


Above: Tesla's app transforms your phone into your Model 3 key (Image: Car and Driver)

This technology not only allows you to eliminate yet another item from your pockets, it presumably allows you to decide how you want your car to lock and unlock (unlike other current vehicles, each of which seems to have a different protocol for unlocking front and rear doors, trunk, etc). It also enables another feature, which Tesla isn’t talking about yet, but would seem to be necessary to use your Model 3 for ride-sharing - remotely enabling a third party to access the vehicle.


Above: How to enter and start the Model 3 (Source: Electrek)

If you’re hungry for even more technical details, you can check out Tesla’s first responders’ guide for Model 3 (thanks to Electrek), which has some nifty diagrams. The first responders’ guide is a document used by firefighters and other emergency personnel who may need to rescue someone or extinguish a fire after a crash.


Above: Safety first, a look at Model 3's ultra high strength steel reinforcements (Source: Electrek)

Electric vehicles present a different set of dangers for first responders - it’s critical for them to know how to disconnect the high-voltage battery after a crash, both to protect themselves from electric shock and to reduce the risk of a battery fire. The first responders’ guide explains how to recognize a Model 3, describes the location of the various high-voltage components, and explains how to safely disconnect them in an emergency situation.

Bonus: Model 3 walk-through videos



Bonus Model 3 walk-through videos from OCDetailing; Editor's Note: To check out more from the Tesla's First Responder's Guide, view the PDF. Also, if you missed it, check out our Model 3 Insider Gems Part 1.