Mec Speed Level Series User Manual

Page 116 Speed Level Series - Service & Parts Manual
January 2019Section 8 - Troubleshooting - 3084RT Models
Problem Possible Cause Remedy/Solution
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 SV4 not functioning
Check voltage and ground to valve
Check for faulty valve spool
Check switch position output from GP400 (See EZ-Cal ID# 2f-18)
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 (EZ-Cal ID# 2d5)
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 (see EZ-Cal ID # 2f-12 & 2f-13)
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 (see EZ-Cal ID#s 2f-12 right &
2f-13 left)
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
Pressure relief valve set too low Set steer relief valve to 2000 p.s.i.
King pin/s seizing in the bore
Disassemble and inspect
Repair
Replace bushings

Mec Speed Level Series Specifications

General

Brand	Mec
Model	Speed Level Series
Category	Boom Lifts
Language	English