JLG 601S ANSI Service Manual - Manual (Page 191)

SECTION 6 - JLG CONTROL SYSTEM (ADE)
3120746 – JLG Lift – 6-17
9/9 Flash code 9/9 indicates problems with the controller. 11
PLATFORM MODULE FAILURE:
hwfs CODE 1 Platform module V(Low) FET has failed
GROUND MODULE FAILURE:
hwfs CODE 1 Ground module V(Low) FET has failed
Table 6-2. Help Fault Codes, Displayed Faults, and Descriptions - Prior to S/N 66939