Adding dual zone climate and ionization to '23-'26 US HEV

I'm trying to talk myself out of this, but I'm going to at least figure out if it's possible and what parts I would need to do it. I'll show my work just in case anyone wants to watch the trainwreck.


Background:
The gen5 has always come with ionization in some markets. It comes on the top trim in Japan(Z trim) and standard on all European cars. It consists of an ion generator mounted into the right-most dash air duct. That makes it driver side on all RHD cars(Japan, UK, etc.) and passenger side on LHD cars(US, most of EU).

The gen5 has always come with dual zone climate in Europe, but it was single zone everywhere else. Also, all European Priuses are PHEVs, so there were no gen5 HEVs with dual zone at all until now.

To change from single zone to dual zone, I think you need to swap three components:
1. A/C box (A/C Radiator Assembly)
2. A/C computer (A/C Amplifier Assembly)
3. Dash Climate Controls (A/C Control Assembly)

This gets complicated because of all the options on all the different versions. After doing a couple days of research, I understand why automakers want to move climate controls to the touchscreen. I've found 14 different gen5 A/C controls and 15 different gen5 A/C computers, and I'm sure I haven't found them all.

I've got a US HEV Limited(H trim), so I need controls that have the buttons for both heated and ventilated seats and is oriented for a LHD car. And I need an A/C computer that's compatible with HEV, climate seats, LHD, dual zone climate, and ionization.



Parts List:

1. A/C box: 87050-47470
- This is a brand new part. It will work in all LHD, dual zone HEVs. The MSRP from a US Toyota dealer will be around $2k, so I'd wait for a 2027 or 2028 HEV to hit the salvage yard. Prices seem to range from $300-$1000 for good condition used A/C boxes. I might try to import it from Japan(they run about $400 there), but I don't think I'll be able to order it through my normal sources as this part does not come on any JDM cars so it won't be in the Toyota Japan system.

2. A/C computer: 886H0-47010
- This is also a brand new part for 2027. Around $1200 new from a US dealership, so I'll be sourcing this from either a junkyard or Japan. They run about $140 new in Japan, so I'm not sure which way I'll go. Probably with a junkyard one from the same car as the A/C box just in case a new one would need to be programmed(I've learned my lesson from the FCTA fiasco).

3. Dash A/C control: 55900-47640
- Yet another brand new part for 2027. I'll probably go new for this one if I can to make my life easier. The previous parts can come out of pretty much any 2027 HEV(LE, XLE, Nightshade, or LTD), but this one has to come from a LTD and nothing else. Should be around $150 if ordered from Japan or $275 if ordered from a US dealership during the best sales. Or I might get lucky and the donor car could turn out to be a LTD.

4. Ion Generator: 88051-46020
- $110 new from Japan, so that will probably be the way I go. The same part is used on some US Toyota and Lexus vehicles, so I might be able to find one in a junkyard. But I think the price for it new from Japan is low enough that I wouldn't try to track down a used one.

5. Ion Duct: 55848-12030
- $1.50 from Japan or $10 MSRP from a US dealership. Not worrying about this one.

6. Replacement RH dash vent duct: 55085-47090
- This might be the hardest part to source. It's only used on LHD European cars, so I can't order it from a US dealership and probably can't import it from Japan. I'd either have to find a vendor in one of the LHD European countries that ships internationally, or find a European salvage yard with a gen5 Prius. Not impossible, but I've never had to source a European part before and don't really know where to start. A comparable part in Japan would be $30 and the US MSRP would be $130.



Installation:

Strangely enough, all the stuff to change from single zone to dual zone would be plug and play. No new wiring needed for that. The A/C box, A/C computer, and climate controls all communicate using multiplex signals, so they use the same simple wiring(1-3 wires each).

Adding ionization, on the other hand, does require adding new wiring, but it's not that much. Two control wires from the A/C computer plus one power and one ground. You could get by with four new wires total, but I'd do it according to the official wiring diagram and use the proper junction connectors and routing. So a total of eight new wires. Still not bad.

But the physical work makes it one of the toughest jobs you can do to a modern car. I'd have to completely pull the entire dash; absolutely everything. When I did my turn signal and power folding mirror upgrade, I pulled the dash pad to get access to the dash wiring. That would only be step one for this project. Once the dash pad is out, I'd have to remove the whole structural brace assembly which includes the entire dash wiring harness. The Car Care Nut has done a few videos where he replaces an A/C box and he always calls them the hardest and most stressful jobs he does. I think I could do it, but it would be the hardest automotive job I've done by a long shot.

On top of that, I'd need the A/C refrigerant removed before I started work and replaced after I was done. And I'd probably need to do a coolant replacement at the same time. Both of these are because I'd need to open up the respective lines when I remove the A/C and heater coils. So that's another few hundred to add onto the cost of the project.

And the final cherry on top is that I would only know for sure if the whole insane idea works after I'm 100% done. There's no way to test the new parts as I go to see if they're compatible with a 2023 HEV. So if I get to the very end(after the system is charged with new refrigerant) and I'm getting errors, the only solution is to redo the entire project and return it to stock(including another drain and recharge of the A/C). That's a big risk even if I'm 90-95% certain the project should work.




On the plus side, I've got plenty of time to talk myself out of this. The limiting factor is going to be finding a 2027 HEV in a junkyard, and that's unlikely to happen for a year or two.