Mec 3072ES - Page 97

PROBLEM REMEDY/SOLUTIONPOSSIBLE CAUSE
"3072ES / 3772ES / 3772ES HD" Service & Parts Manual October 2008
Page 4-31
Lift/Lower
Platform will not
Raise
Excessive weight on Platform
Lift Relief valve out of adjustment
Lift Valve SV-1 not energized
Lowering valve SV-5 stuck open
(located at base of lift cylinder/s)
Level Sensor out of level
(platform elevated above 10 feet)
Main system pressure inadequate
Batteries Discharged
System Interuption
Platform will not
lower or lowers
slowly
Lowers but not
completely (3772ES)
Emergency lowering
not working
Reduce weight to within platform capacity
Adjust relief valve to rated capacity
Check wiring to lift valve
Check EZ-Cal message or flash code
Check and remove contamination from valve/s.
E-Down cable damaged (3072ES only)
Reposition machine to firm level surface.
Check level sensor function using EZ-Cal
Check pump output pressure
Check battery voltage.
Clean, service and charge batteries.
Check HELP or MODE message on EZ-Cal
Maintenance Lock in maintenance position
Lowering valve not energized
Lowering valve not shifting
Lowering orifice (ORF-3) plugged
System Interuption
Return Maintenance Lock to the stowed position
Check wiring to lowering valve/s located on lift cylinder/s.
Check for EZ-Cal message or flash code
Clean debris.
Check for damage.
Replace
Clean orifice/s located inside hose fitting on each lift cylinder.
Check HELP or MODE message on EZ-Cal
Down valve on one cylinder inoperative
E-Down cable broken or frayed (3072)
Lowering valve not shifting
Lowering orifice plugged
Check valve coils as described in Platform will not lower or lowers slowly
Replace E-Down cable
Clean debris.
Check for damage.
Replace
Clean orifice
3772ES ONLY E-Down battery discharged
Valve coil failed on either cylinder
Charge battery.
Check charge diode & connections
Test, replace
Lowers but not
completely
Down valve on one cylinder inoperative Check valve coils, wiring
TROUBLE Table continued
continued…