SYSTEM / Control System Pump Learning Control Purpose: Detects pressure which is necessary to pump control, when the pump control sole- noid valve is activated. Operation: 1. When the following conditions exist and the learning switch in the rear console is turned to the pump learning position (opposite to E), MC acti- vates the pump control solenoid valve. 2. Therefore, the spool in pump control solenoid valve is operated. 3. The regulator pressure sensor detects variable pressure at this time and sends the signal ac- cording to each pressure to MC. 4. MC records electrical current and pressure when the pump control solenoid valve is activated. Condition: Engine:
Running Engine Control Dial: Fast Idle Auto-Idle Switch: OFF Power Mode Switch HP Mode Pressure Sensor: Output zero. (The control lever is in neutral.) Hydraulic Oil Temperature: 50 ± 5 ° C (122 ± 41 ° F) Pilot Shut-Off Lever: LOCK Position IMPORTANT: Perform the pump learning if the following work is done. (Refer to the T/M [Troubleshooting] section.) Replace the pump, pump regulator and pump control solenoid valve Replace MC NOTE: The pump learning is not required when the batteries are replaced. T2-2-40