Water entered the whole car

Was the car submerged?How wet did it get, was the PCM under water, I need some details here please.

Your model, should be on the passengers side.

Here is a diagram to help show you (below):

The PCM will have to removed and tested for water damage this is a specialist job. A replacement PCM will have to be re flashed to suit your car and then the rest of the car needs to be inspected for further immersion damage including the transmission if the car was under water the Tom will probably also be damaged as well depending on salt or fresh water damage there may be a lot of electrical problems costing a considerable amount of money to repair. Do not throw money at this car with out first making sure it is worth it

Module re-flash is a dealer only job, you need access to Toyota data base. It is built into the PCM ignition functions.

Please let us know what happens so it will help others.

Cheers, Ken

If this car was flood damaged you are fighting a losing battle. Every electronic system will need to be stripped apart, flushed dried and tested. Every connection will have to be checked. The engine might survive but it will at minimum need to have the oil changed and lot's of luck that the silt and dirt carried in the water does not destroy the bearings in the first few turns. Transmission will need to have a full fluid change as well.
HVAC system will need to be removed so that it can all be flushed out and cleaned. Interior and carpets will also need to be done.

The best option for a modern car that has been submerged is to strip it for body parts and toss all of the electronics and interior in the scrap heap.

Your choice but I have seen people spend a lot of time and effort on flood cars and still have multiple issues. That water gets into everything and the silt in it does as well. Inside the mechanical parts like bearings and seals the silt acts like sandpaper.
It settles out in the heater/AC unit and in the carpets and padding, Seats mold on the inside. Your exhaust system will have a bunch of silt in it which likely will damage the converter. Inside every body panel and cavity that stuff will lay. Not a bid deal until you consider what was in the water and makes up that silt.
Then you have all the wiring and computers in there as well. Miss one connection that has water/silt in it and you have a problem.
It is the big issue with cars from the flood areas from the various hurricanes. It would not be much of an issue on old cars, they did not have miles of wiring and motors and computers controlling everything.

It really stinks, but in 99.99999% of the cases, unless you have tons of money or the car is some ultra rare vehicle that just has to be saved by someone with lots of money, it is better to part them out. The pictures are just some of the items that you would need to clean and test before you even tried anything.