"My USB`s not working"に関する回答This is a common issue on the L505D that happens from a capacitor breaking off of the motherboard. The easiest way to fix it is to replace the motherboard. This video shows how to actually repair the motherboard via soldering, but I don’t recommend anyone without much soldering experience to follow this guide. Unfortunately, the motherboards for the L505D, at present time, are rather rare and expensive, so I would simply replace the laptop as a whole.
"Why is my laptop not turning on but the indicator lights flash?"に関する回答Short answer: The motherboard is bad. I find that common on the L505D, unfortunately. Long answer: From what I’ve seen with these, the Toshiba L505D is affected by the good old lead-free solder failure issue that Xbox 360s and many computers have. I’ve saved at least one, if not two or more L505Ds following this reflow procedure with great results. But I’d only pursue this if you or someone you know has good experience with soldering. It’s important to note that a preheater, in my experience, helps the results to last much more than otherwise. If you don’t have one, I wouldn’t bother. Regardless, it is an older laptop, so I’d look into replacing it. If you’re looking for something inexpensive, there are many great refurbished laptops out there that can be had for less than a brand new one, and as far as data transfer goes, all you need is a SATA-to-USB adapter to plug your L505D’s HDD into your replacement laptop. It’s easy to get to the HDD on the L505D. Regardless of which method you choose, good luck!