Komatsu 170-3 Series Shop Manual page 187

TROUBLESHOOTING
Action by controller
• Yellow lamp lights up
• Limits high idling speed to 1,500 rpm
• Red lamp lights up
• Red lamp lights up
• Recognizes throttle signal as 0%
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• Red lamp lights up
• Carries out open control of fuel rail
• Red lamp lights up
• Carries out open control of fuel rail
• Red lamp lights up
• Sets current to fuel rail actuator to 0 A
• Yellow lamp lights up
• Limits engine speed to 1500 rpm
• Yellow lamp lights up
• Limits maximum injection amount to 217
3
mm /st
• Yellow lamp lights up
• Limits maximum injection amount to 217
3
mm /st
• Yellow lamp lights up
170-3 SERIES
ACTION TAKEN BY CONTROLLER AND CONDITION OF
MACHINE WHEN ERROR CODE IS DISPLAYED
Problem that appears on machine
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Probable cause
• Defective timing rail pressure sensor
• Defective wiring harness and connector
of timing rail pressure sensor circuit
• Defective engine controller
• Excessive suction resistance of fuel filter
• Defective idling validation switch
• Defective wiring harness and connector
of idling validation switch
• Defective engine controller
• Defective idling validation switch
• Defective wiring harness and connector
of idling validation switch
• Defective engine controller
• Defective battery
• Blown fuse
• Defective wiring harness and connector
of controller power source circuit
• Defective engine controller
• Defective battery
• Blown fuse
• Defective wiring harness and connector
of controller power source circuit
• Defective engine controller
• Defective fuel rail pressure sensor
• Defective wiring harness and connector
of fuel rail pressure sensor circuit
• Defective engine controller
• Defective fuel rail pressure sensor
• Defective wiring harness and connector
of fuel rail pressure sensor circuit
• Defective engine controller
• Defective fuel rail actuator
• Defective wiring harness and connector
of fuel rail actuator circuit
• Defective engine controller
• Excessive negative pressure at inlet port
of fuel pump
• Defective timing rail actuator or clogged
screen
• Broken injector O-ring
• Defective engine controller
• Excessive negative pressure at inlet port
of fuel pump
• Defective fuel rail actuator or clogged
screen
• Broken injector O-ring
• Defective engine controller
• Excessive negative pressure at inlet port
of fuel pump
• Defective fuel rail actuator or clogged
screen
• Broken injector O-ring
• Defective engine controller
• Defective dual output solenoid A
• Defective wiring harness and connector
of dual output solenoid A circuit
• Defective engine controller
12-217