I have a 2009 Toyota Avalon limited trim with 199k miles. The car has been getting progressively louder when moving up to a loud roar at highway speeds, and seems to get louder when going around curves. Also the radiator fans won’t turn on at all, even if you turn on the AC full blast which normally would activate them immediately. It’s never overheated; I’ve been switching the heater on full blast with the AC turned off, so the heater core has been my makeshift radiator, and just venting the heat out the windows. The multi-link fuse is unbroken and the relay has been replaced, but still no fan power. These issues are probably unrelated but both started around the same time. Is it worth fixing or do I bite the bullet and buy something else? The engine and transmission, suspension etc. are all still going strong. I saw your recent video on the 2007 Avalon and now I never want to get rid of this thing!
Is there a reason to replace the entire radiator and fan assembly for the fans just not turning on?
No. Is the radiator clogged? Leaking? If not there is no reason to replace it.
As far as the fans, the problem could be just a bad relay, bad temperature switch, or even a blown fuse. Diagnosis is needed to pinpoint the cause. You can easily test the fans to see if they're working when directly powered. If they do work then it's a matter of tracing out the circuit fault. Or you could hook up a new circuit with a temperature sensor and/or a manual switch to turn the fans on.
https://www.youtube.com/watch?v=iUuK5t-9fiQ
https://www.youtube.com/watch?v=9Hj7Ri3TXhc
Why not simply replace the noisy wheel bearing(s) and trace the electrical fault causing the fans to not operate?
Alright, I got it in the air and did the “shake test” pushing/pulling on the tires from side to side and top to bottom. The front passenger wheel had noticeable play in all directions, at least half an inch or so. The rest didn’t seem to have any wobble. I ordered a replacement bearing/hub/knuckle assembly, hope that’s the only one going bad. As for the radiator fans, I had a mechanic check it out and they’re trying to sell me a new radiator, fan assembly, etc. Is there a reason to replace the entire radiator and fan assembly for the fans just not turning on? That seemed excessive to me given the radiator is absolutely still functioning since it cools just fine while the car is in motion.