TM 5-3805-280-24-1
Sub-System Diagnostics
Turn key switch OFF.
ARM REGENERATIVE
YES: Harness and engine
PROPORTIONAL
and pump controller are
SOLENOID (Y9)
Install proportional solenoid test harness JT07352 in series with wiring harness and
OK.
HARNESS CHECK
sense solenoid.
NO: Harness or engine
Connect voltmeter to test harness jacks.
and pump controller has
failed. Repair or replace.
Start engine and move arm all the way out and boom down.
Adjust idle to slow (voltmeter reading approximately 7 volts).
Move boom up and arm in at the same time.
Does voltmeter read higher voltage (approximately 9 volts) while boom and arm are
moving?
9015
15
93
1/1
POWER BOOST
Turn key switch OFF.
YES: Solenoid is OK. Go
PROPORTIONAL
to next check.
SOLENOID (Y5) CHECK
Remove wire clip from bottom of solenoid harness
connector.
NO: Solenoid has failed.
Replace.
Disconnect harness from solenoid.
Connect ohmmeter to solenoid terminals.
T7491AC
UN08APR91
Does ohmmeter read approximately 24 ohms?
1/1
Turn key switch OFF.
POWER BOOST
YES: Harness and engine
PROPORTIONAL
and pump controller are
SOLENOID (Y5)
OK.
Install proportional solenoid test harness JT07352 in series with wiring harness and
HARNESS CHECK
sense solenoid.
NO: Harness or engine
and pump controller has
Connect voltmeter to test harness jacks.
failed. Repair or replace.
Start engine and observe voltmeter while pressing power boost switch.
Does voltmeter read approximately 5 volts when switch is not pressed, and
approximately 9 volts when switch is pressed?
Hold power boost switch pressed.
Does the voltage drop to 5 volts after approximately 8 seconds?
1/1
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