I'm having problems with my Sienna overheating because to fans are not coming on. I did have 3 codes come up when I scanned it (P0100,P0110,P0115) I've replaced the mass air flow sensor and temp sensor then cleaned the codes. Drove the van around for a bit but it was still overheating and not kicking on the fans. I then replaced the fan switch sensor and all the relays that have anything to do with the fans. When I ground the wire going to the fan switch both fans will come on, so I know the fans works. The fans will come on occasionally if I turn the ignition all the way off, then put the ignition into the on position but not at a predicable frequency.
Here is a short video going over all of this. https://youtu.be/1it790gy7Yo
Not sure what I should do next. I would hate to have to take it to a dealership.
Well you did the obvious problems what's I'm assuming happened which can happen is the switches or something shorted out then that wiped out the driver circuit in the computer so rather than by an expensive new computer you could merely hook up a toggle switch with wires and fuse and the battery to the fans and run them directly with the toggle switch turn them on when you start the car and turn them off when you turn the car off
