Hitachi ZAXIS 135US-5B Operator's Manual page 359

 Fusible Link (Main Fuse)
In case the starter won't rotate even if the key switch is
turned to the START position, fusible link may be the cause
of the trouble. Remove the cover next to the engine coolant
reservoir to check the fuse. Replace it if blown.
21- + Side (Red)
45 A
22- – Side (Black)
65 A
MAINTENANCE
7-85
21 22
Battery
ZX135US-5B
ZX225US-5B, 225USLC-5B
M1U1-07-023
MDCN-07-054
22 21