Tesla Quietly Rolls Out Hardware 4.5: 5 Things You Need to Know

Tesla is infamous for never adhering to traditional model years, opting instead for continuous iteration. Just when owners were getting comfortable with Hardware 4.0 (HW4), reports are surfacing of a new interim update dubbed "Hardware 4.5" (AP45) appearing in newly delivered vehicles. If you recently took delivery of a Model Y, you might already have it sitting in your driveway without realizing it.

Here is a breakdown of everything we know so far about this stealthy hardware update, how to find it, and what it means for the future of Full Self-Driving (FSD).

1. The "AP45" Label Confirms Its Existence

Rumors began swirling when a new Tesla owner, identified as EricSun on X (formerly Twitter), posted photos of their Fremont-built Model Y manufactured in late January. The standout feature? A label on the car computer clearly reading "AP45."

While Tesla hasn't made a formal announcement, the label "AP45" strongly suggests a revision distinct from the standard AP4 (Hardware 4). This unit was found in a Model Y Performance, indicating that higher-trim recently built models might be the first to receive this updated computer.

2. It Is Officially Listed in the Parts Catalog

This isn't just a misprint or a one-off prototype. The "Hardware 4.5" designation has officially appeared in Tesla's Electronic Parts Catalog (EPC).

According to the catalog, the component is listed as "Car Computer - Left Hand Drive - Provisioned - Hardware 4.5" with a price tag of roughly $2,300. This backend confirmation validates that Tesla is treating this as a distinct hardware generation, or at least a significant enough revision to warrant its own part number.

3. Physical Changes: New Camera Housing

Aside from the internal computer, there are visible external changes associated with these newer builds. The vehicles appear to sport a new front camera housing design.

Interestingly, while the front housing has been updated, reports indicate that these units do not feature rear camera washers or repeater washers. This mix of new housing with the omission of certain cleaning features suggests Tesla is streamlining the sensor suite, possibly relying on improved camera sensors or software to mitigate the need for washers.

4. How to Check if You Have HW4.5

If you took delivery of a Tesla in December, January, or February, you might be curious if your car is equipped with AP45. Checking is surprisingly simple and requires no tools, though you should proceed with caution.

The car computer is located inside the cabin, specifically behind the upper carpet liner below the glovebox (in the passenger footwell).

• Step 1: Locate the upper carpet liner that houses the footwell light and vents.
• Step 2: The liner is held in place by a push clip and magnets. Gently pull it down.
• Step 3: Look for the sticker on the metal box (the computer) to see if it reads "AP45."

Warning: Be careful not to pull too hard to the left, as the speaker wire is connected there.

5. It Is Likely a Bridge to AI5

Why release Hardware 4.5 now? The general consensus among the Tesla hacker community, including "GreenTheOnly," is that this serves as an interim upgrade before the major leap to AI5 (Hardware 5).

Speculation suggests this unit might utilize a 3-SoC (System on Chip) design, which was previously spotted in software code. While Elon Musk has stated that Hardware 5 is next, AP45 likely allows Tesla to optimize production or introduce minor processing improvements using current supply chains before the next-generation architecture is ready for mass production.

Conclusion

While finding "Hardware 4.5" in your new Tesla is a nice bonus, it likely represents an incremental manufacturing optimization rather than a revolutionary leap in capabilities. As always with Tesla, the best advice is to buy the car when you need it rather than waiting for the next hardware iteration, as the technology is in a constant state of flux.