JLG G6-42A Service Manual - Manual (Page 218)

Electrical System
9-54 G6-42A, G9-43A, G10-43A
9.11.6 Engine Oil Pressure Sender
a. Engine Oil Pressure Sender 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.
3. Open the engine cover. Allow system fluids to cool.
4. Properly disconnect the battery.
5. The engine oil pressure sender (2) is threaded into
the engine block. Remove the sender.
b. Engine Oil Pressure Sender Inspection and
Replacement
Inspect the sender and the wiring harness connector
terminals for continuity. Replace a defective or faulty
sender with a new part.
c. Engine Oil Pressure Sender Installation and
Testing
1. Thread the engine oil pressure sender into the
engine block snugly, then connect the sender
connector to the wiring harness connector.
2. Properly connect the battery.
3. Check for proper oil level.
4. Start the engine, and observe the operator’s display
for warning indication. If the sender is not defective,
the problem could be elsewhere; possibly in a
shorted wire, improper-running engine, low oil,
obstructed or faulty oil pump, defective instrument
display.
5. Close and secure the engine cover.
6. Remove the Do Not Operate Tags from both the
ignition key switch and the steering wheel.
9.11.7 Fuel Level Sender
a. Fuel Level Indicator Testing
1. The fuel level sender wiring harness leads can be
accessed from the top of the fuel tank. Disconnect
the fuel level sender wiring harness leads. With the
help of an assistant, touch both harness leads
together.
2. From the operator’s cab, have the assistant turn the
ignition key switch to the RUN position. DO NOT
start the engine. Observe the fuel level indicator
needle on the operator’s instrument cluster. The
reading must be at the FULL mark.
3. Turn the ignition key switch to the OFF position. The
fuel level indicator needle should return to the
EMPTY position.
b. Fuel Level Circuit Tests
If the fuel level sender (3) is suspected of giving a false
reading, perform the following checks:
1. If the fuel level indicator needle does not move,
check the fuel tank for fuel.
2. Check for loose or defective wiring, faulty ground
connections, and corrosion on the fuel tank sender
and wiring lead.
3. If the fuel level indicator needle does not move after
the ignition key switch is turned to the RUN position,
use a test lamp to determine whether current is
flowing from the ignition switch to the fuel level
sender.
MY4340
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