most of the people dont know that short circuit procedure is not recomended for the mp4 or mp5 players
if you have the SLIDE PANEL MP4 or MP5 that doesn't require any short circuit thing.Just you have to know the key or the key combinations to make your mp4 go to software mode if that is the software problem.

First of all i have a player like that and once i used a different charger. the charger had different polarity and when i plugged it in the mp5 nothing happened. then i noticed that near the arrow buttons it became hot. When i opened it i found that i fried a small chip.
From that time on it didn't charge any more. I tried replacing the small chip but could not recognize it. Then after some testing with multimeter I found that if you solder a diode instead of this it began to charge but the charging animation didn't turn on.

The second thing. The button you are searching is probably hidden. You'll have to reach it by inserting a small screw driver in the line-out jack and then connect to usb.

Hope this helps!!

thinks a lot for this help,
do you mean the line-out jack of earphone ?

for the small chip is it resistance ,can you show me in the
picture where is it, it is very small and because i have a little knowledge in éléctronics,

meanwhile i try a test taking care with a multimeter using a manuel joined to it.

No the line out of the video near the usb port and charging port.

For now i do not have any pictures of the small chip but I will upload some soon!!

thinks a lot.
i'll try and i'll tell you if it work or not.

hello
i had found button when i open it ,i tried puching it and plug usb after but not thing windows dont detect it or no thing happened
only when i short circuit a chip sometimes windows detect it but dont found driver,i tries all driver adfus,driver wich i had foud it here for sunplus but always no thing.

Hello. If you found a way for windows to detect as something else (I think webcam) use this driver The button you found you have to keep pressing it when connecting to usb.

hello
yes i did ,i keep pressing the button like you said but always not thing , i used the driver wich you upload it when i short circuit a chip always no thing.
the windows xp dont reconize a driver,
i think i must find a good driver if someone have it

hello
until now no driver found and no solution ,the mp5 stay in drawer.