Page 115
45-J Desel - Servce & Parts Manual
January 2022
Secton 19 - Troubleshootng
Problem
Possible Cause
Remedy/Solution
Platform Auto-Level
Platform will not remain
level while elevating or
lowering platform (level
cylinder moving too slow
or fast)
Flow compensator valve (22) not
shifting completely
Clean debris. Check for damage/replace.
Adjustments in GP400 incorrect
Refer to Adjustments Flow Chart column 4F for settings that will allow
leveling to be close then make slight changes until operating correctly.
Contact MEC Technical Support for assistance if needed.
Pump faulty
Test/replace pump
Problem
Possible Cause
Remedy/Solution
Platform Manual Level
Platform level operates
automatically but not
manually
Platform level toggle switch
inoperative
Check output from toggle using EZ-Cal. See I.D.# 2C-1, P15-3 (up) P15-6
(down) for lower control operation or 2c-2, P14-11 (up) or P14-12 (down)
from upper controls.
System Interlock
Check EZ-Cal HELP message for interlock
Problem
Possible Cause
Remedy/Solution
Turntable Rotate
Turntable will not rotate
either direction
Turntable rotate joystick inoperative
Check joystick output using EZ-Cal. See 2D2 P7-2 for signal.
Rotate valve (11) not energizing.
Check wiring to valve Check GP400 output using EZ-Cal.
See 2E1 P4-7 (left) and P4-8 (right).
Rotate valve (11) not shifting.
Clean debris. Check for damage/replace.
Internal damage or failure of rotator
Inspect/clean/repair
System interlock
Check EZ-Cal HELP messages for interlock
Turntable will rotate in one
direction only
Rotate valve (11) not energizing
Check wiring to valve
Rotate valve (11) not shifting
Clean debris. Check for damage/replace.
Mechanical interference in rotator
Inspect, clean or repair
System interlock
Check EZ-Cal HELP messages for interlock
Problem
Possible Cause
Remedy/Solution
Platform Rotate
Platform will not rotate
either direction
Platform rotate joystick inoperative
Check joystick output using EZ-Cal.
See 2D2 P6-2 for signal.
Rotate valve (20-1) not energizing
Check wiring to valve Check GP400 output using EZ-Cal.
See 2E1 P5-1 (left) and P5-4 (right)
Rotate valve (20-1) not shifting
Clean debris. Check for damage/replace.
Internal damage or failure of rotator
Inspect, clean or repair
Flow Compensator valve (22) not
shifting
Clean debris. Check for damage/replace.
System interlock
Check EZ-Cal HELP messages for interlock
Platform will rotate in one
direction only
Rotate valve (20-1) not energizing
Check wiring to valve
Rotate valve (20-1) not shifting
Clean debris. Check for damage/replace.
Mechanical interference in rotator
Inspect, clean or repair
System interlock
Check EZ-Cal HELP messages for interlock
Problem
Possible Cause
Remedy/Solution
Drive
No drive operation
Planetary hub bypass engaged
Check bypass plates located in the center of each planetary hub. Should
be convex. Turn over if not.
System interlock
Check EZ-Cal HELP messages for interlock
Hydraulic oil incorrect for severe
low temperatures
Use hydraulic tank warmer if equipped. Operate drive continuously until
drive begins to operate.
