SO, I just installed a set of FN f(x) Pros in matte bronze on my 4Runner, and had new TPMS sensors installed so I can sell my old wheels and tires with the sensors.

I ordered the Denso 550-0105 TPMS sensors from Summit Racing. Denso's web site doesn't include 2018 4Runners, so I went with the '17 PN.

Had the dealership slap everything together, after taking pictures of all the sensor ID's to program into Techstream when I got home so I could save $120.

Well, I go into the TPMS registration utility, enter the TPMS ID numbers, and then check the Data screen, and they show up as being registered, but they are not showing any pressure (N/A is what is displayed), so I check the diagnostic code, and its giving a Code C2126 Transmitter ID not Received (Main).

WTH is going on? I have scoured YouTube, and I cant find anything dealing with this error. I watched a video of a guy installing brand new sensors on a newer Taco, using TechStream, and those sensors worked just fine.

What am I missing? What am I doing wrong?
Google has been no help.

ETA: do the sensors, when first registered have to correspond to a specific location, such as Registered ID Code 1 have to be LF, 2. RF. 3 LR, 4 RR or something like that?
The video I referenced earlier didn't specify that particular question, he just wrote down the sensor numbers and then input them into Techstream.

I've never messed around with my sensors, or the TPMS settings in techstream.

Sounds like there's a lot of variables. Sensors could be bad, or be the wrong P/N. Wrong freq? Perhaps the code on the sensor isn't what the T4R is really expecting. HEX vs Dec or some other conversion. (just guessing)

It would be easier, cheaper and less complicated to just move the OEM sensors to the new wheels and let the buyer deal with new sensors......

Why not just get the rebuild kit for the TPMS sensors and keep your old ones? I’ve sold several sets of wheels and tires, not once has anyone explicitly requested I leave my TPMS sensors on the wheels. I unfortunately cracked one of my sensors when installing my SCS wheels and KM3s. I bought a replacement from Olathe Toyota for $60 dollars shipped. My local dealer wanted $135 Ended up borrowing my Matco distributors scan tool to write the sensor ID and had no issues with it yet.

These sensors are Denso, which is the OEM supplier. Same PN as the '17.
runs on the same frequency (315mhz) can't change inputs between HEX or DEC.

Because I didn't want to swap over the sensors and sell the OE wheels without them.

Using TechStream to register the TPMS sensors SHOULD be pretty straight forward. But like other things computer related, it's never as simple as it should be.

Well I am pretty sure they just need to be woken up.

I too just bought a new set of sensors for a second set of wheels. I picked up a ATEQ VT31 tpms scanner, like all of these plasticky cheaply built fk’n bs tools, you either drop $300-500 on one that does it all or three tools that do a few things. I opted for the cheapest route, this activates, reads ID’s, and checks pressures.

I had discount mount and balance. I took them home and put the tires on myself, I read each sensor with the scanner, set it’s position in the tool, started techstream, ran the I’d utility, set the id’s and lol TS crashed. Started it again and it had accepted the new sensors.