Oshkosh JLG 400S, Service And Maintenance Manual

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SECTION 3 - CHASSIS & TURNTABLE
3-174 – JLG Lift – 3120895
Normally Closed Switch
• Key-On, Engine On
• System Mode= “Running”
• Warm engine at idle to normal
operating temperature
• Increase RPM above limit set
in diagnostic calibration
Does DTC 524
reset ?
Intermittent Problem
No
• Key Off
• Disconnect harness from Oil Pressure switch
• Jumper Oil Pressure signal wire to ground
• Clear DTC 524
• Key On, Engine On
• System Mode= “Running”
• Operate engine et idle for at least one minute
• Increase RPM above limit set in diagnostic calibration
Yes
Does DTC 524
reset?
• Faulty connection at sensor
• Faulty ECM
• Faulty Oil Pressure Switch (open circuit)
• Faulty engine oiling system (verify with
mechanical gauge)
No
Yes
Does DMM indicate a
resistance < 5.0 ohms?
• Disconnect wireharness header from ECM
• Carefully remove yellow lock from header
at device output terminal
• CAREFULLY check resistance between
Oil Pressure signal at ECM header and
signal at sensor.
NOTE: DO NOT
INSERT probe or object into terminals
as this will cause the terminal to
spread and may no longer make
contact with ECM pin. Spread pins will
void warranty! Probe on the side of
terminal.
• Faulty harness
(open circuit)
No
Yes