Pressure Gauge Does Not Register Pressure; Pump Pressure Builds Very Slowly Or Not At All; Lube Cycle Timer Not Operating; Timer Stays Timed Out - Komatsu 930E-2 Shop Manual

POSSIBLE CAUSES
TROUBLE: Pressure Gauge Does Not Register Pressure
No system pressure to the pump motor.
No 24 VDC signal at pump solenoid.
Pressure reducing valve set too low.
Relay (RB7K5) may be defective.
TROUBLE: Pump Pressure Builds Very Slowly Or Not At All
No signal at RB7K5 relay.
Pressure switch may be defective
Pressure reducing valve may be set too low.
Grease viscosity may be too high for temperature at
which pump is operating.
Pump inlet check or outlet check may have foreign
matter trapped causing leakage.
Lubricant supply line leaks or is broken.
Insufficient hydraulic oil supply.
TROUBLE: Lube Cycle Timer Not Operating
Timer BAT (-) connection is not on grounded member.
Timer BAT (+) connection not on circuit continuously
connected to BAT (+) terminal during operation of
vehicle.
Loose wire connections at any of the timer terminals.
TROUBLE: Timer Stays Timed Out
Commutation failure in timer caused by damaged com-
ponent.
Output relay contacts welded shut caused by extended
short to ground.
Solenoid valve connected to "IGN" terminal of timer
instead of terminal marked "SOL".
P3- 14
SUGGESTED CORRECTIVE ACTION
Check hydraulic hose from steering system.
Determine problem in 24 VDC electric system.
Refer to "Pressure Control Valve Adjustment".
Replace relay.
Check Timer and CB7.
Replace pressure switch.
Refer to "Pressure Control Valve Adjustment".
Replace grease with a lower viscosity lubricant.
Remove, inspect and clean, if necessary.
Inspect sealing surfaces between checks. Replace if
rough or pitted.
Repair lubricant supply line
Check oil pressure and flow to motor.
Connect to good ground.
Establish direct connection between Timer BAT (+)
connection and 24 V BAT (+) terminal.
Secure wire connections.
Replace Timer.
Replace Timer
Correct wiring hook-up.
Automatic Lubrication System P03018 4/00