Main Boom Trn Angle Sw/Sensor Disagreement - JLG 1250AJP Troubleshooting Manual

SECTION 1 - FAULT DICTIONARY AND SELECTED TROUBLESHOOTING
Note Pretest Instructions
1.191.22 Disconnect PVG enable
[X068]. Start machine. Fully
stow boom, center turntable
between rear wheels. ANA-
LYZER ⇒ ACCESS LEVEL 1
⇒ SERVICE MODE ⇒ MAIN
LIFT. Enter code 55050.
1.191.23 Ensure machine is in same
condition as step 1.191.22
Pretest Instructions. Return
boom to fully stowed posi-
tion. Ground meter. Take the
following readings by back-
probing the contact in ques-
tion. (See Section 6.
Multimeter Basics on Pg.
319 for details.)

1.192 MAIN BOOM TRN ANGLE SW/SENSOR DISAGREEMENT

Flash Code: 8-4
Main boom transport angle switch and sensor disagreement. The main boom transport angle switch changed states outside
of the +4/-8° tolerance window to the stored calibration point. This could indicate a problem with the main boom transport
switch, the main boom angle sensor, or the calibration stored transport switch point.
Note Pretest Instructions
1.192.1
1.192.2
1.192.3 Retract and lower boom
completely
1.192.4 Remove sensor coupler
1.192.5 Retract and lower boom
completely
1.192.6 Retract and lower boom
completely
1-108
Test
WHEN THE STABILITY CONTROL
IS OFF, THE MACHINE WILL TIP IF
USED INCORRECTLY.
Measure voltage across PVG enable [X068]
while operating boom lift momentarily. Only lift
a few feet. Does the meter read about 12VDC?
WHEN THE STABILITY CONTROL
IS OFF, THE MACHINE WILL TIP IF
USED INCORRECTLY.
Measure voltage at ground control module J2
pin 31 [X002.31.pin] by backprobing while
operating boom lift. Only lift a few feet. Does
the meter read about 12VDC?
Test
Are the following faults present? MAIN
TRANSPORT ANGLE SWITCH FAILED, main
angle sensor faults
Examine the coupling, rotary sensor, mount-
ing blocks and the cross bolt in the main boom
pivot pin for loose hardware or damage. See
Figure 2-5. Boom Area Connectors on Pg. 185
for details. Is there any?
Is the timing mark for the sensor in the proper
place? See Figure 2-5. Boom Area Connectors
on Pg. 185 for details.
Is it between 2.6 and 2.8 inches?
Is there 0.075+/-0.030 inches clearance
between the sensor mount and the main boom
pivot doubler?
Remove main transport angle switch [X051]
mount. is the sensor flush +/- 0.015 inches
with bottom of counterbore in sensor mount?
1250AJP
Result Corrective Action
Yes Replace any main lift PVG valve [X074] shock
valve that was not in specified range as recorded
in step 1.191.5
No Keep machine in same condition. Go to step
1.191.23.
Yes Turn off machine. Repair/replace harness
between ground control module J2 [X002] and
PVG enable [X068]
No Turn off machine. Replace ground control mod-
ule.
Result Corrective Action
Yes Troubleshoot those first
No Go to step 1.192.2
Yes Repair as needed
No Go to step 1.192.3
Yes Go to step 1.192.4
No Re-align mark on shaft to the mark on the face
near "R", for right side, on label. It is on the side
opposite of the connector. Go to step 1.192.8
Yes Go to step 1.192.5
No Replace any coupler outside the given length
Yes Go to step 1.192.6
No Adjust sensor mount to achieve proper distance.
Yes Do not re-install sensor mount. Go to step
1.192.7.
No Adjust sensor to achieve proper distance.
3128411