The question is: What are the correct power suppply specifications. Just telling me some numbers, without stating which one is the correct and which one the wrong power supply, doesn't really help much. if you did that, then we can talk about the diode, if this talk is necessary at all then. Are you sure that the adapter is working? Try the loopback test. If that works, you probably have connected RX and TX the wrong way on the HDD. Yes I'm sure because i use it to conect with phones and its working.I try to change RX and TX but its not comunicate.I try with HDD connect to see is it give me that error LED:.... but nothing