Boom Unlock Procedure; Initial Conditions; Procedure - JLG 1850SJ Service And Maintenance Manual

6.10 BOOM UNLOCK PROCEDURE

If the fault "LIFT CYLINDER OVER PRESSURE" or "WRONG TELE
RESPONSE" is active, then the boom will be trapped in trans-
port.
To clear these faults, the Boom Unlock Procedure must be fol-
lowed.

Initial Conditions

Before performing the Boom Unlock Procedure, the following
conditions must be met:
• Booms Sensors, Jib Sensors, Axle Sensor and tilt sensor cal-
ibrations must be successfully completed
• The Boom is operating in the BCS Normal Mode
• The parking brake is not reporting a short to battery from
the UGM or the UCM
• The main boom sensor is reading less than 600"
• The jib is fully retracted
• The main boom sensor is reading less than 7 degrees
• The axles are completely extended
• The machine control system indicates that it is not tilted
• The turntable is centered between the rear tires
• Ground Mode is selected

Procedure

NOTE: During the calibration, if the ESC key is pressed after the
procedure is started, the calibration will be aborted and
exit back to the "UNLOCK BOOM" prompt.
NOTE: The envelope, moment and appropriate faults will continu-
ously be monitored after the initial conditions are satisfied.
If at any time during the test these conditions change to an
unsafe state (communications lost, envelope violation,
moment violation etc.) the Calibration will abort and the
analyzer will display "ENVLP VIOLATION".
1. Using the analyzer, enter access level 1. Unlock Boom
can be found under the Calibrations menu.
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SECTION 6 - JLG CONTROL SYSTEM
2. Once the operator selects the UNLOCK BOOM option,
the screen will read:
Pressing will cause the boom to check the initial
conditions listed above. If any of the calibrations have
not been completed "CAL. BOOM" will be displayed. If
there is a problem with the envelope, moment or any of
the supporting sensors (including loss of communica-
tions) "CHECK FAULTS" will be displayed. If the parking
brake is shorted anywhere in the system "PARK BRAKE
FAULT" will be displayed. If the jib is not fully retracted
"JIB TELE IN" will be displayed. If the telescope is reading
more than 600", "MAIN TELE IN" will be displayed. If the
main boom angle sensors are reading more than 7
degrees, "MAIN LIFT DOWN" will be displayed, if the
axles are not extended "EXTEND AXLES" will be dis-
played. If the DOS switch is not indicating in line and the
angles are not within 10° of inline "ALIGN TURNTABLE"
will be displayed. If the chassis tilt is tilted "LEVEL
MACHINE" will be displayed. If the machine is in plat-
form mode. "SELECT GRND MODE" will be displayed. If
none of the above faults are present, the test will move
on to the next step. As each fault is cleared, the system
will make sure no other faults are active. During this
time the latched faults from If the fault "LIFT CYLINDER
OVER PRESSURE" or "WRONG TELE RESPONSE" is active,
then the boom will be trapped in transport. These faults
will be latched through key-cycle.
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