Komatsu ecot3 PC300-8, Shop Manual

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40 Troubleshooting SEN02627-04
PC300, 350-8
7
Troubles that occur when controller power supply of pump controller is defective
a
The controller power supply (F01-17) of the pump controller drives the controller system. Accordingly, if
it is turned off, the controller cannot control the system and the troubles shown below occur simulta-
neously (The following is an example of the troubles).
q
The working mode cannot be changed.
q
The auto-decelerator does not work or is not reset.
q
The travel speed does not change.
q
The power maximizing function does not work.
q
The swing holding brake cannot be reset automatically.
q
The machine deviates during travel.
Troubles that occur when solenoid power supply of pump controller is defective
a
The solenoid power supply (F01-2) of the pump controller is used by the controller to drive the solenoids
and relays. Accordingly, if the solenoid power supply is turned off, when the controller outputs the power
to the solenoids or relays, the power is not supplied to any of the solenoids and relays and all or some of
the following failure codes are displayed simultaneously.
q
[DW43KA], [DW43KB]: Travel speed solenoid system
q
[DW45KA], [DW45KB]: Swing holding brake solenoid system
q
[DW91KA], [DW91KB]: Travel junction solenoid system
q
[DWA2KA], [DWA2KB]: Service solenoid system
q
[DWK0KA], [DWK0KB]: 2-stage relief solenoid system
q
[DXA0KA], [DXA0KB]: PC-EPC (F) solenoid system
q
[DXE0KA], [DXE0KB]: LS-EPC solenoid system
q
[DXE4KA], [DXE4KB]: Service current EPC system (if attachment is installed)
q
[DWJ0KA], [DWJ0KB]: Merge-divider main solenoid system
a
If the above problems occur, check the related fuse (F01-2) and inlet voltage of the pump controller.
1) Disconnect connectors CP01 and CP02 of the controller and connect a T-adapter to the wiring har-
ness side.
2) Turn the starting switch ON.
3) Measure the voltage between each of pins CP02 (116), (118), (121) and each of pins CP01 (2), (5).
* Pins CP02 (116), (118), (121) are the power supply and pins CP01 (2), (5) are the chassis ground.
* If the voltage is 20 – 30 V, it is normal.