Electrical Key & Tpms Receiver

Hey everyone, I'm new to this forms site and I'm having a very specific problem. When I got my Tacoma it came with a tire pressure light on but the tires are good and I am unable to program key fobs to the truck. My father took my truck to the dealership to try and program keys, they were unable and diagnosed the problem saying it was a "ECU transponder". Unfortunately when I look it up it has nothing to do with the keyless entry. I've scoured the internet and found "receiver assembly, electrical Key & TPMS" which sounds promising. Only issue is that I can not find where it is in my truck. Also my key fobs work and so do my tp sensors. Any help or suggestions would be great.

 

The two issues are probably unrelated.
TPMS warning light will come on if the battery is dead in one of the sensors. They have a finite life and if they are the original ones that came with the truck in 2017 one or more of them could definitely be dead

 

Sounds strange the dealer can’t resolve this, I’d try another.

 

The dealer could fix it but it's more of the difference between 500 plus and less than 120 for the part so I'm trying not to pay an arm and a leg. The dealer was able to check the Tpms in the tire and they claimed that all four are good. Thank you though.