trusting the old reliable mechanical way was a safer approach that going electronic…at least they have the mechanical backup installed but kind of hard to press down vs just pulling the old style mechanical door handle
Remedy now available to existing owners. You should be able to schedule with your dealership. I just scheduled mine, though I don't know for certain if all Priuses(2023-26) are getting them together or if there are phases. The Prius is so low production that I have to assume Toyota is just doing them all in one batch. After all, it's rear door switches on 140k cars, not full engine replacements on 500k+ trucks/SUVs. (My VIN is under 3000, so I'd be in either the first group or the last if Toyota is doing this in phases.)
It's supposed to be a 1.8hr job. That's what Toyota pays the dealership(actually 1.7hr for the repair, 0.1hr for administrative costs). The process includes: 1. Removing the rear seats completely(seat backs and bottom) 2. Remove pretty much all the trim surrounding the rear doors(lower B-pillar trim, floor trim, trim between rear seat and door) 3. A new wiring harness is run alongside the original harness from a point halfway up the B-pillar, under the door, and up the rear wheelwell. 4. A new relay is installed at the end of the new wire harness up near the shoulder seatbelt tensioner. 5. Repeat on the other side and put everything back together. I have no idea how a relay placed on the body side of the door and plugged into nothing but a wiring harness that connects to nothing except a different part of a wiring harness is going to prevent an actuator in the door itself from activating, but I'm not a vehicle electrical engineer. I assumed they were going to replace the door switches again, but the doors aren't touched at all. And I don't know why the new relay needs to be installed where it is when it's not connected to anything but the new harness. There's nothing in the dealer or technical instructions about how or why it works, only how to install. On the positive side, it's the perfect time to get the fuel tank recall done if you've been putting it off. Both recalls involve completely removing the rear seat.
Oh, yours is a 2026. I think yours was built after the recall. edit: Oh, yeah. You're well clear. The recall was for 2023-24 models. Actually 2023 Prius and Prius Primes, and some 2024 Primes. But the Primes only had to have a software update. It was the HEV's that needed something added to the fuel tank.
Educated guess from the description is that the relay intercepts power to the actuator, only letting it get power on some condition like the vehicle being in Park. Presumably this new harness is being connected inline at a connection point. The actual new wire harness routing is a bit mysterious. If it isn't actually connecting to anything in the B pillar, then maybe it's just about finding a physical space to put the relay module. Maybe the harness is making the connection between: a place in the existing wiring harness where you can both intercept the actuator power and pick up the when-to-allow-power signal; and a space big enough to hold the power interceptor module.
Sorry I wasn't clear. It DOES connect to the wiring harnesses in the B-pillar. And then it goes from there, under the door, and up the wheelwell where it terminates in a relay. But that end of the new harness doesn't connect to anything EXCEPT the new relay. So why not install the relay in the B-pillar area and not bother running it under the door? I'm sure there's a reason, but I don't know what it is. I'm going to go ahead and link the technical instructions. I'm trying to do that a bit less(especially since my annual subscription expired over a year ago), but this one is so complicated you almost need the visuals to understand.
Clarification doesn't change my guess, apart from swapping the locations - there's not physically room for the relay at the interception point.. Not sure I totally buy that though. (But given how concerned they are about properly securing things, maybe it could be stuffed in somehow, but they wouldn't be happy with the longevity, including overstressing the existing wiring)
I just figured there'd be enough room near the base of the B pillar under the trim if the relay's position didn't matter. So they'd need a half meter of wiring instead of two meters. And a shorter wiring run would have certainly made it easier for the dealership techs. But I guess the only thing that matters at the end of the day is that it works.
