I need to replace the fuse in the motherboard of acer aspire 5535 laptop

SOURCE: my acer aspire 5772 shut down

The motherboard must be faulty for them to give you that advice. you can look for people who actually repair those motherboards or replace it.

SOURCE: how to remove and replace the keyboard in my acer

This is a tricky operation, requiring a degree of experience.

The bezel between the top has to be removed. Open the cover all the way, so it's in line with the base. Then GENTLY pry the bezel by lifting first one side then the other; carefully loosen the four tabs under the keyboard. remove and save the two screws holding the keyboard down; move the keyboard slightly towards the display, and lift from the rear (spacebar side). There is a flat cable attaching the keyboard to the motherboard, held in by a "white-ish" clip. Gently loosen one side, and the keyboard will be free of the unit.

NOTE: this cable has to be PRECISELY positioned by this clip, or your new keyboard won't work correctly. DO NOT reassemble until you have tested the unit!

SOURCE: restore back to factory settings

From Acer direct

The other way before Vista starts up is to tap ALT + F10 (at the same time repeatedly) when the computer is first switched on.. The window of opportunity is very small, so this may take a few attempts

Once you have tapped both the ALT and F10 repeatedly, you may see a screen showing:

“Edit Boot options for Microsoft Windows Vista”

If you see this, unfortunately, you have missed the window of opportunity, and you need to restart, and try again.

If you see this:
“Edit Boot options for Windows Setup” OR “Edit Boot options for Acer eRecovery”

Then it indicates that you have tapped the ALT + F10 correctly, and all you now need to do is press “Enter” and the Recovery program should load on your screen after a short pause..

In some cases, you may need to remove the battery (for notebooks only) and run the machine directly from the mains.

The Disk2Disk recovery feature allows you to recover the system without recovery CDs.
This will return your system to factory settings and will delete everything stored on the machine.
If possible we strongly advise backing up anything important on your machine before starting the recovery process.

SOURCE: hi can anyone tell me where the motherboard fuse

My understanding is there is no fuse to replace like you think. There is a fusible link soldered into the mother board that will have to be replaced if that's the issue.

SOURCE: Want Acer Aspire 5532-5535 manual

Here you can download the ASPIRE Series Manual

http://global-download.acer.com/GDFiles/Document/Generic%20UG/Generic%20UG_Acer_1.0_A_A.zip?acerid=633952301071877862&Step1=Notebook&Step2=Aspire&Step3=Aspire 5532&OS=V10&LC=en&BC=Acer&SC=PA_7