JLG 3969electric ANSI Service Manual - Manual (Page 33)

SECTION 3 - TROUBLESHOOTING
3120768 – JLGSizzor –
3-3
Platform raises or lowers erratically Enable switch not activated Activate enable switch
Function not activated within 3 seconds after
enable switch was depressed Reactivate enable switch
Enable switch not functioning properly replace enable switch circuit card
Hydraulic system low replenish oil as necessary
Restricted or broken hydraulic line or fitting Clean, repair or replace as necessary
Control valve not functioning properly Repair or replace valve
Worn seals in lift cylinder Replace seals
Cylinder not functioning properly Repair or replace cylinder
Platform drifts down Worn seals in lift cylinder Replace seals
Manual descent valve open Close manual descent valve
High drive does not operate below horizontal Damaged wiring on limit switch Repair or replace wiring
Damaged limit switch Replace limit switch
Table 3-1. Platform Assembly Troubleshooting
TROUBLE PROBABLE CAUSE REMEDY