Komatsu PC88MR-10 Shop Manual page 256

10 Structure and function
Electrical control system
Control function when pump secondary drive switch is "ON"
If the controller has trouble and the main pump does not operate normally and the machine does not work,
the operator can operate the machine temporarily with the absorption torque equivalent to E mode by
operating pump secondary drive switch (1).
At this time, since a constant current flows from the battery to the PC-EPC valve, only the PC-EPC valve
senses oil pressure.
a: Emergency (when abnormal)
b: Normal (when normal)
a Pump secondary drive switch (1) is alternative type. If the operator operates the machine with this switch
at the "Emergency (a)" position while the machine is normal, action level "L03" appears on the display.
10-178 PC88MR-10