4 auxiliary hydraulic pressure release switch, 5 parking brake switch, Auxiliary hydraulic pressure release switch – Lull 944E-42 Service Manual User Manual

Page 181: Parking brake switch

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9-23

944E-42

Electrical System

9.11.4

Auxiliary Hydraulic Pressure Release
Switch

The auxiliary hydraulic pressure release switch (1) is
located in the upper bank of switches on the right side of
the dash and is pressed into a rectangular switch bezel.

a. 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. Properly disconnect the batteries.

5. Carefully pry the auxiliary hydraulic pressure release

switch and wiring out of the mounting hole.

6. Label and disconnect the wiring from the switch.

Remove the switch from the machine.

b. Disassembly

DO NOT disassemble the switch. The switch is not
serviceable. Replace switch if found to be defective.

c. Inspection and Replacement

Inspect switch wiring for continuity and shorting. Replace
a defective or faulty switch with a new part.

d. Installation and Testing

1. Connect the previously labeled wires to the switch.

2. Make sure the symbol is at the bottom of the switch,

then press the switch into place in the benzel.

3. Properly connect the batteries.

4. The ignition switch must be in the RUN position. The

engine can be either idling or shut OFF. Press and
hold the momentary auxiliary hydraulic pressure
release switch for two seconds to release trapped
pressure in the auxiliary hydraulic system. If the two
auxiliary hydraulic couplings can now be easily
connected or disconnected, the switch is operating
properly.

5. Close and secure the engine cover.

9.11.5

Parking Brake Switch

The park brake switch (2) is located on the dash to the left
of the steering column and is pressed into a rectangular
switch bezel.

a. 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. Properly disconnect the batteries.

5. Carefully pry the park brake switch and wiring out of

the mounting hole.

6. Label and disconnect the wiring from the switch.

Remove the switch from the machine.

b. Disassembly

DO NOT disassemble the switch. The switch is not
serviceable. Replace switch if found to be defective.

OU0502

1

OU0382

5

F

1/2

E

D

PARK BRAKE INDICATOR

LIGHT

2

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