I have a Toshiba 46HM95 TV that sounds like a lawn mower when you start it up...this just started and it sounds like its coming from the cooling fan...is that possible and can I fix it myself?

No particular reason. There was a class action law suit filed against Toshiba for this. You can do 2 things to lengthen the lamp life though. Go into the TV menu and turn off the quick start feature. You should also switch the lamp to low power mode. Switch it back to high power mode when the picture gets too dark for your viewing pleasure. I hope this was helpful.

It sounds Lamp is dead in your TV, how old is this TV and did you replaced its lamp recently?
Click Part Store to see required lamp image and price info.

I would try replacing the lamp.

check the system control board

my 46HM95 was humming also, I have the extended warranty and the company came out and diagnosed it as the light engine. the part was backordered and it was just fixed today, it was ordered back in February. Problem was solved.

That could be either the ballast, or colorwheel. Does the sound get louder at the rear of the tv or louder in front. let me know I may be able to help you.

I have the same thing, mine is the cooling fan for the lamp. If the sound continues for a short time after you turn off the TV then this is the most likely cause as the cooling fan will continue to run for a short time to cool off the bulb. I have looked into replacing mine, the part runs around $50 but I can't say yet how easy it is to replace yet.

The light engine part number is 234054 and cost $456.00

possible ballast problem or cooling fans not operating

Change lamp fan #23587525