Lost only fob; need to understand ECU reprogramming...

Hi folks,

Terribly keen for any advice - I read everything in the Prius C sub that seemed related and it just seems there's not a lot documented about this particular situation. In other searches on the site in all subs, there seems to be a bit of conflicting information so I'm not sure which end is up.

TL;DR - I lost the only fob for our JDM (Japanese Domestic Market?) 2013 Toyota Aqua. Local dealership is crap. I can do the work replace the ECU and am importing a second hand unit from Japan (with at least one fob programmed to it, and one fob to program) but there seems to be a vague "reprogramming" that needs to take place for the car to run. Is that something I can do if I bought TechStream (and borrowed a neighbours PC - none of this stuff seems to work on macOS). If not, is the reprogramming done through OBD II - thus I can put the car back together before towing and possibly get it up onto a hire trailer vs paying a legit tow company to make a 120km round trip? Or does it have to be done direct through the ECU (which, now that I ask, doesn't seem to make sense but I'm asking anyways) thus I should leave it apart?

Now for the extra details:

We're in rural New Zealand and bought our Aqua a year ago as my husband does the two hour round trip to town three or four days a week (it has almost literally paid for itself in the petrol savings from the 320i he was driving before that). We went to the beach on Thursday and in a manoeuvre one would call ridiculous if they saw it on a TV program, I managed to grab the fob in my pocket for safe keeping while crossing a stream, lose my balance, ripped my hand out of my pocket in effort to steady myself, and catapulted said fob into a stream where it would have promptly rushed out to the ocean never to be seen again.

I'll try to remember that this is a post to ask for advice and not someplace to process my emotional trauma around the situation. Let's just say it's now 11am on Monday morning, the car has been sitting in storage since Thursday night rapidly eating away at the $1000 policy max payout for lost keys from our insurance company (though I've been trying to get them to tow it to ours for the last two days but the insurance company hasn't responded because of the weekend), the local dealership has said it would be 6-8 weeks to get a new OEM part imported from Japan and then, upon further probing, told me there were no secondhand parts available even though I found a plethora of them I can import from Japan in 10 days after about 5 minutes of Googling. They were also just generally awful humans to deal with.

It's clear that I'm going to have to do this repair myself, and it seems that while it's a time consuming process to pull the dash to replace the ECU, it's not all that difficult - except said reprogramming.

So, as above, I'm guessing that reprogramming is done through OBD II? It's not actually something done on the ECU itself, yes? Is there a combination of hardware and software that would allow me to handle it? It's not as simple as resetting the immobiliser by putting a jumper between the two ports that are widely referenced in other posts so I won't try to recall them here as I'd hate to put out bad information...?

Any advice would be super appreciated.

Thanks heaps.

 

Totally makes sense. At least I can put it back together.

Didn't even think about sideloading. My 10 year old Air has Intel. It's been super slow when I've done it before, but worth it to not give any money to the dealership.

Cheers!

 

Just to tie off -

Got a tip from the tow truck driver about a locksmith they use at the tow yard. Called him Monday midday. He came out yesterday afternoon and got us two working fobs in no time.

I guess I should've known better than to call the dealership in the first place, but I'm just amazed that they would tell me my only option was to wait 6-8 weeks and expect me to be ok with it.

 

It was 1,500NZD. 1,100 for the first fob, and 400 for the second that we always should have had but didn't. Everything is much more expensive here than the US though, so I don't know how it might compare. Thankfully all the towing, storage, and $900 of the locksmith are covered by our insurance.

I did also file a consumer complaint against the Toyota dealership. NZ law is pretty clear about consumer rights. The dealership not only provided false information but also omitted important information, knowingly or not, for the express purpose of their financial gain. Fingers crossed the powers that be look into it.