DETAILED CONTROLS AND GAUGES OPERATION Engine Oil Change Monitor (Only if Equipped) This monitor (2) warns the operator that the set time for the engine oil change has passed. If the set time (125, 250, 500 H) passes after the engine oil is replaced, this lamp lights up. If the lamp lights up, change the engine oil. When you want to change the oil replacement interval, consult Komatsu Ltd. or its distributor. 3-6