OM2044 Safety - Section 20 Page 20-11 PRECAUTIONS FOR MAINTENANCE BEFORE PERFORMING MAINTENANCE Electrical Systems Isolation Stopping The Engine Before Service Isolation box (6, Figure 20-1) contains master disconnect switch (3), starter disconnect switch (4) and propel lockout lever (5). The isolation box is located on top of the front bumper, on the left hand side. Move both disconnect switches and the propel lockout lever to the OFF position to disable the 24VDC electrical system, starters and the AC electric drive system. When the switches and propel lockout lever are in the OFF position, LED lights (8) will be illuminated.
The battery disconnect switches and propel lockout lever can be padlocked in the OFF position to prevent unauthorized truck operation. When the switches and the propel lockout lever are in the ON position, LED lights (7) will be illuminated. Refer to the following table to ensure the correct disconnect is used to isolate a desired circuit or system. Before performing inspections or maintenance, stop the machine on firm, flat ground. Lower the dump body, place the directional control lever to the PARK position (this will apply the parking brake), and turn the key switch to the OFF position and wait for the engine to stop.
Wait two minutes after the engine has stopped, and if no warning lights illuminate, then turn the battery disconnect switches to the OFF position. Verify that the disconnects are functioning. Place wheel chocks around the wheels to prevent the truck from rolling. If the engine must be operated during maintenance, always move the directional control lever to the PARK position (this will apply the parking brake). Always perform this work with two people. One person must be in the operator's seat to stop the engine if necessary. Never move any controls not related to the task at hand during these situations.
Apply the propel lockout lever (5, Figure 20-1) to prevent the truck from moving if the engine must operate during maintenance. When the propel lockout lever is in the OFF position and LED light (8) is illuminated, the drive system is locked out and the truck will not propel. When the propel lockout lever is in the ON position and LED light (7) is illuminated, the drive system is active and the truck can be driven. NOTE: This is the recommended usage of the battery disconnect and propel lockout switches. Local regulations may be different. When servicing the machine, use care not to touch any moving parts. Never wear loose clothing.
When performing service with the dump body raised, always place the dump lever in the HOLD position, and apply the lock (if equipped). Install the body-up safety cable securely.
Action Recommended Isolation 24V Electrical Troubleshooting Starter Lockout 24V Electrical Maintenance/Repair Master Lockout High Voltage/Propulsion Troubleshooting None High Voltage Maintenance/Repair Master Lockout Hydraulic Troubleshooting Propel Lockout Hydraulic Maintenance/Repair Starter Lockout Engine Troubleshooting Propel Lockout Engine Repair Master Lockout Mechanical Repair Starter Lockout Weld Repair Master Lockout & Alternator Isolation Fueling Starter Lockout Lube/General Maintenance Starter Lockout Shift Change Walk Around Starter Lockout Oil Sample Collection Propel Lockout