Platform Leveling Down Function Inoperative - JLG T350 Troubleshooting Manual

1.20 PLATFORM LEVELING DOWN FUNCTION INOPERATIVE

Step Pretest Instructions
1.20.1
1.20.2 Engage enable and Level Up
switch
1.20.3 Install a 0 to 5000 PSI (345
bar) pressure gauge at the
manifold G port
1.20.4 Plumb a 0 to 5000 PSI (345
bar) pressure gauge into the
manifold P port
1.20.5 Put boom in transport and
activate Platform Level Up to
relieve pressure. Some work-
ing pressure will still be in the
line. Install a 0 to 5000 PSI
(345 bar) pressure gauge at
the manifold GB port
3121203
Test
Basic check of likely causes
DC - Is pump motor running?
Gas - Is engine running at high
idle
Engage the enable and Level
Down switch. Check the pres-
sure.
Engage the enable and Level
Down switch. Check pressure
at manifold P port
Engage the enable and Level
Down switch. Check pressure
at manifold GB port. Relieve the
pressure before removing the
gauge.
T350 T500J
SECTION 1 - TROUBLESHOOTING BY FUNCTION
Result
Yes
No
Yes
No
Above Min. Level Down Pressure
psi (bar)
Below Min. Level Down Pressure
psi (bar)
Above Min. Level Down Pressure
psi (bar)
Below Min. Level Down Pressure
psi (bar)
Above Min. Level Down Pressure
psi (bar)
Below Min. Level Down Pressure
psi (bar)
Corrective Action
Possible Causes: 4.1.32, 4.1.33,
4.1.37
Go to step 1.20.3
See 1.2 Pump Motor Will Not Operate -
DC Powered Models
Go to step 1.20.3
See 1.8 Engine High Idle Inoperative -
Engine Models
Go to step 1.20.5
Go to step 1.20.4
Possible Causes: 4.1.38, 4.1.45,
4.1.74, 4.1.40, 4.1.10, 4.1.43
Possible Causes: 4.1.46, 4.1.47,
4.1.74, 4.1.45, 4.1.39, 4.1.10
Possible Causes: 4.1.49, 4.1.48,
4.1.41
Possible Causes: 4.1.42, 4.1.57,
4.1.44, 4.1.56
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