I have a roland e96 that showed the message_INTERNAL BATTERY WEAK every time i switch on and the display of screen is empty

1. Check the power cable and ensure it is securely connected to both the amp and the power outlet. 2. Check the fuse and replace it if needed. 3. Check the power switch and ensure it is in the correct position. 4. Check the battery (if applicable) and replace it if needed. 5. If the amp is still not turning on, contact Roland customer service for further assistance.

You need to replace the battery. It will most likely be a coin sized battery in a slip in holder on the main board. If you need help, here is ROland Customer Service contact info-
Support Roland
After that, you can reset the E96 back to the factory settings by following the directions here-
Roland 96 Initializing the 70 86 96 Restoring the Factory Settings...

If you are referring to the User Data, then yes that would be gone.
Time to reset and start re-programming

Most likely the acid ate the internal power supply, but if you can dis-assemble it and clean any trace of gunk with a toothbrush and electronic cleaner, including the fuse and it's contacts, maybe you'll get lucky.

The unit name is part of the boot sequence, it should go beyond that and boot up completely. If it gets stuck there, there is surely some problem. Maybe a depleted internal battery, I don't know. Ask a local service center, maybe there's a combination of buttons you could check out while on the phone prior to bringing it in for repair...

Well I did it. Remove 14 screws marked with arrows. Be careful separating the top from the bottom as there are several cables to deal with. The only cable I disconnected was the larger Ribbon Cable. The CR 2032 battery slides out by lifting the end of the retainer about 1/16 of an inch. Then simply slide in the new battery and make sure it is seated. Then just reassemble.

Check the power adapter at the coaxial plug end that plugs into keyboard- is there power there? If so, is the socket on the keyboard loose at all? If so- the socket may be broken, If there is no power there, you either need a new power supply or you need to open it up to see if it is just the fues in that supply that failed.

If the plug inserts snugly as it did when new and it dopes not power up, the issue may be the power switch on the back- it may have dirty or corroded contacts- cycling the switch on and off several times rapidly should clean it.

If it still does not power up, there should be a fuse internal to the keyboard that would require you open it up to check it. If it is not under warranty, this is not an issue- if it is under warranty, it is something that should be checked in the shop.

Thee internal fuse should have protected it.

Here is schematic:

http://elektrotanya.com/roland_cube-20_combo_sch.gif/download.html

Scroll down on page and click on "Get Manual"

The procedure at this link shows you a battery replacement procedure that should work for you:http://ztup.com/Roland-D110-Battery-Replacement-Guide.htm You will need to design new user patches if you didn't back them up.

The polarity switch selects whether the pressure causes a positive or negative electrical spike. This can affect whether your drum MODULE fires on the hit or when the hit is lifted.

Thin plastic triggers are an electret plastic and have piezoelectric properties.when their shape is changed by pressure, etc.