are there fuses for the 5v wire?? i tried to fix my n900 by myself an had everything soldered together but usb was not regognised.... BUT

when i use a cutoff usb cable and short the Data wires it boots when i put in a battery ... that means the data pins are correct soldered ...

but i have connection with gnd and +5v (from cut off usb cable to testpoints on the pcb) too.

that means:

the usb is soldered it correctly.

data wires are regognised

issue could be an fuse...

i never saw an fused gnd

so it must be a fuse somewhere on +5v...
or an broken USB cotroller.

someone know where the fuses are??
how can i test the usb controller??