SECTION 4 | TECHNICAL REFERENCES
Does machine
lower?
Not
at all
Descent speed
slow or erratic?
Are any structural
members bent?
Contact manufacturer to
arrange replacement.
Is there a
restriction in
hydraulic hose?
Yes
Yes
Does the up/
down switch
appear
damaged?
Yes
Creeps down? Or
Goes up and Comes
Back Down?
Has key
switch been
turned off?
Is an E-Stop
activated?
Is battery
charged?
Is emergency
down valve
open?
Yes
Faulty down
valve?
Electrical problem?
Disconnect coil.
Check if unit stops drifting.
Check voltage at coil
—
should be
0 V when not energized.
Foreign matter
lodged in up or
down valve?
Damaged cylinder or
damaged seal in cylinder?
Run unit up and then check for
oil flow out of return line. Bad
cylinder seal if oil is flowing
from return line.
Down Valve Coil
mounting nut too tight?
Nut should only be lightly
snug: 3.4 Nm.
No
Yes
Faulty check valve
in pump?
Listen carefully near motor
when not energized
—
may be
running backwards
Yes
Starts
descending, then
stops?
In
maintenance
chock in
place?
Yes
No
Does the proximity
sensor or actuating
parts appear
damaged?
Will Manual
Override lower
the platform?
Turn key to
upper or lower
ON position.
Pull out
emergency
stop button at
upper and
lower controls.
No
No
No
Level of skill with
hydraulic maintenance?
Not experienced
with hydraulics
Check manual override cable, lever, and fastening points
Yes
Replace rocker
switch at upper
or lower control.
Yes
Yes
Flowchart: IQ LIFT-Lowering
Troubleshooting Step 2B: Lowering
Troubleshooting Flowcharts--General Notes:
Inspect parts for visible damage as they are encountered.
After each step, check if problem has been indentified and/or resolved.
If so, make the recommended fix or see a referenced document.
If not, continue troubleshooting.
If a part has been identified as needing replacement, see the
Parts Manual
to
identify part number to order.
If any wiring or components have been altered from the original
manufacture, problems may not be identifiable.
WARNING
Any modification on this machine without
the express consent of the manufacturer
is prohibited.
WARNING
Failure to comply with safety precautions
may result in damage, injury, or death.
Refer to Maintenance Manual for
complete warnings
See also
Wiring Diagram Electrical Schematic
And
Hydraulic Schematic
WARNING
: Set up for maintenance safety:
Remove load from platform.
Check for overhead obstructions.
Platform movement may occur.
Never Reach between scissors links or prop up
platform unless maintenance pins are in place.
Yes, but
not properly
No
No
Check wiring
connections in
lowering
components.
See
Electrical
Schematic
WARNING:
Double check that
maintenance chock is in place
Yes
Yes
No
Yes
Charge battery.
Yes
No
No
OK
No
Yes
Level of skill
with hydraulic
maintenance?
Check Hydraulic
Circuit. (Additional
tools required,
higher level of skill
required)
Refer to
Hydraulic
Schematic
Are power
connections to
lowering circuit and
switches functioning
properly?
Contact your
Dealer or
Manufacturer
for
troubleshooting
assistance.
Does the
armguard Limit
switch appear
damaged?
No
Yes
No
No
No
Experienced with
Hydraulic systems
Experienced
With hydraulic
systems
Not experienced
With hydraulics
Remove
ML Pins
Yes
Replace
limit switch
at base
Yes
No
Close
emergency
down valve.
Check cable
connections.
Flush down valve by
simultaneously pressing up
switch at base and down
switch on platform control
for 30 sec.
Replace
hydraulic hose
Disassemble and clean.
Look for residue in screen
and on O-ring or damage
to O-ring.
Replace coil
and lightly
tighten nut.
No
Yes or Don’t know
Replace
down valve.
Might be able to repair with seal
kit;, probably need to replace
cylinder. If walls inside cylinder
are scratched or pitted, cylinder
needs replacement.
Yes
Replace
pump.
Replace
down
valve
No
No
Reference Revision P01
Reference Revision P01
Is there a
diagnostic flash
code or
message?
Use
diagnostic
message to
identify
problem
Replace
sensor or
actuating
parts
Replace or repair
identified problem.
See
Parts Manual
.
MAINTENANCE & TROUBLESHOOTING
IQ LIFT
SUPO-759
REV C
31
