JLG G12-55A Service Manual - Manual (Page 177)

9-35 G10-55A, G12-55A
Electrical System
6. Unplug the wiring harness connector from the
engine oil pressure sender (4) or switch (5).
7. John Deere/Perkins - The engine oil pressure
sender/switch is threaded into a fitting on the bracket
weldment. Remove the sender/switch.
Cummins - The engine oil pressure sender is
threaded into the engine block directly above the oil
filter. 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 fitting
or 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.
9.10.8 Fuel Level Sender
a. Fuel Level Indicator Testing
The fuel level sender wiring harness leads can be
accessed from the top of the fuel tank.
1. Loosen and remove he four screws securing the fuel
sender cover (6).
2. Disconnect the fuel level sender wiring harness
leads (7) from the fuel sender (8). With the help of an
assistant, touch both harness leads together.
3. 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.
4. Turn the ignition key switch to the OFF position. The
fuel level indicator needle should return to the
EMPTY position.
MY1810
MY4640
5
4
4
JOHN DEERE PERKINS
CUMMINS
4
MY4340
6
8
7