JLG G12-55A AccuPlace Service Manual - Manual (Page 148)

Electrical System
9.30 G10-55A & G12-55A AccuPlace
2. Place a Do Not Operate Tag on both the ignition key
switch and the steering wheel, stating that the
machine should not be operated.
3. Open the engine cover. Allow the system fluids to
cool.
4. Disconnect the battery negative (-) cable from the
battery negative (-) terminal.
5. Disconnect the wiring connector at the lift isolation
solenoid lead.
6. Remove the nut on the end of the lift isolation coil
(9).
7. Remove the lift isolation coil.
8. Remove the lift isolation solenoid (10). (Remove only
if the electrical coil is found to not be faulty.)
b. Disassembly
DO NOT disassemble the solenoid. The solenoid is not
serviceable. Replace solenoid if found to be defective.
c. Lift Isolation Solenoid Valve Installation
Note: ALWAYS replace seals, o-rings, gaskets, etc.,
with new parts to help ensure proper sealing and
operation. Lubricate seals and o-rings with clean
hydraulic oil.
1. If necessary, install the lift isolation solenoid in its
original orientation.
2. Slide the lift isolation coil over the solenoid. Tighten
the nut to secure the solenoid. DO NOT overtighten.
3. Connect the wiring connector to the lift isolation coil
lead.
4. Connect the battery negative (-) cable at the battery
negative (-) terminal.
5. Close and secure the engine cover.
9.11.7 Steer Solenoid Valves
a. Steer Solenoid Valve Removal
1. Park the machine on a firm, level surface, level the
machine, fully retract the boom, lower the boom,
place the transmission control lever in
(N) NEUTRAL, engage the park brake and shut the
engine OFF.
2. Place a Do Not Operate Tag on both the ignition key
switch and the steering wheel, stating that the
machine should not be operated.
3. Open the engine cover. Allow the system fluids to
cool.
4. Disconnect the battery negative (-) cable from the
battery negative (-) terminal.
5. Disconnect the wiring connector at the two steer
solenoid leads.
6. Remove the nut on the end of the steer coil (11).
7. Remove the lift isolation coil.
8. Remove the steer solenoid (12). (Remove only if the
electrical coil is found to not be faulty.)
b. Disassembly
DO NOT disassemble the solenoid. The solenoid is not
serviceable. Replace solenoid if found to be defective.
c. Steer Solenoid Valve Installation
Note: ALWAYS replace seals, o-rings, gaskets, etc.,
with new parts to help ensure proper sealing and
operation. Lubricate seals and o-rings with clean
hydraulic oil.
MAP0450
9
10
9
10
MAP0460
11
12
11
12