Mec 4069RT - Page 120

“4069RT” Service and Parts ManualMarch 2014
Page 4-24
TROUBLESHOOTING -- TROUBLESHOOTING CHART
No low speed
(high torque mode)
Speed/Torque switch inoperative Check continuity through Speed Select switch with wires
disconnected terminals 2 & 1
Valve SV3 not functioning Check for 12 volts and ground to valve
Check for faulty valve spool
Check switch position output from GP400
(See EZ-cal ID# 2f-17)
EP1 poppet valve not functioning Check or replace valve (see hyd schematic for location)
No Mid Speed SV3 or SV4 powered and/or shifted These valves should not have 12 volts
In mid-speed, check valve function
Speed/Torque selector switch malfunction Terminals 1 or 3 are common with terminal 2 when switch
is in mid position
No High Speed Speed/Torque selector switch inoperative Check continuity through Speed Select switch with wires
disconnected terminals 2 & 3
Valve not functioning Check voltage and ground to valve
Check for faulty valve spool
Check switch position output from GP400
EP2 poppet valve not functioning Check or replace valve
No Speed Selection Limit switch not functioning Check limit switch located on left rear of base
Check limit switch input with EZ-Cal
Steer
No steer in either
direction
Lift/Drive selector switch in the Lift
position
Switch must be in Drive position for steer operation
Joystick rocker switch inoperative Check continuity through rocker switch on green and yellow
wires (right & left) with blue wire (input).
Steering valve inoperative Check steering valve for power or damage
Check switch position output from GP400
System Interruption Check HELP messages using EZ-Cal
Hoses connected incorrectly See hydraulic section for proper connection
Pressure relief valve set too low Set steer relief valve to 2000 p.s.i.
Steers in one direction
only
Steering valve inoperative or stuck Inspect – replace steering valve
No power to steering coil Check for power and ground in both directions.
Repair wiring
Check switch position output from GP400
System Interruption Check HELP and MODE message on EZ-Cal
Steers, but not fully, or
steers slowly
One or both steering cylinder seals failed Check steering cylinder seals – replace
King pin/s seizing in the bore Disassemble and inspect
Repair
Replace bushings
Outriggers deploy
unevenly and/or unit
will not level
Unit on excessive angle Relocate machine to more level ground.
Outrigger extend valve sticking Inspect/replace deploy valve found at each outrigger
cylinder.
Proximity switch failed open or closed Check proximity switches. Switches should be closed with
outriggers retracted.
Tilt sensor not properly calibrated Recalibrate Level (see instructions in Section 2 of this
manual).
Damage to one or more outrigger legs Inspect and replace as needed.
Outrigger hoses connected incorrectly See Section 1 of this manual for hose routing detail.
Pressure relief valve set too low Set main relief valve RV1 to 3500PSI.
Table 4-1:
Troubleshooting Chart
PROBLEM POSSIBLE CAUSE REMEDY/SOLUTION