H-35 Oil Flow In Attachment Circuit Cannot Be Controlled - Komatsu PC88MR-10 Shop Manual

H-35 Oil flow in attachment circuit cannot be controlled

Failure Oil flow in attachment circuit cannot be controlled.
For machines with provision for attachment, oil flow rate of attachment circuit varies
depending on selected working mode.
Related
Procedure for oil flow rate adjustment differs between working modes, ATT mode and B
information
mode. For details, see Operation and Maintenance Manual.
If failure codes are displayed, perform troubleshooting for them first. (DXE4KA, DXE4KB)
No. Cause
Malfunction of ATT
1
control EPC valve
PC88MR-10
Troubleshooting of hydraulic and mechanical system (H-
Procedure, measuring location, criteria, and remarks
a Be ready with engine stopped, then perform troubleshooting with engine at
high idle.
ATT control EPC
valve output
pressure
a If output pressure of EPC valve is 0 MPa, check "Service solenoid2
current""Service solenoid5 current" with monitoring function. (monitoring
code: 01700,01702)
If current value is 0.3 to 0.91 A, EPC valve may be defective.
Check that output pressure changes according to selected oil flow setting.
ATT control
switch
At NEUTRAL
(full stroke)
ATT control
switch
Depressed
(full stroke)
40 Troubleshooting
mode)
(PC88MR-HBE-400-A-Z0-A)
0 MPa {0 kg/cm 2 }
Pressure
corresponding to
selected oil flow
setting
40-513