Hitachi ZAXIS 120-6 class Operator's Manual page 250

Disconnecting the booster cables
1. Disconnect black negative (-) cable (2) from the machine
frame first.
2. Disconnect the other end of black negative (-) cable (2)
from the booster batteries.
3. Disconnect red positive (+) cable (1) from the booster
batteries.
4. Disconnect red positive (+) cable (1) from the machine
batteries.
OPERATING THE ENGINE
3-12
1
Booster Batteries
(Black)
To Upperstructure Frame of the Machine
2
Disconnect Booster Cable from Frame First
Disconnecting the booster cables
Battery Disconnect Switch
(Red)
Machine Batteries
MDC1-03-001