Main Power Circuit Troubleshooting; Machine Will Not Power Up - Oshkosh Corporation JLG 20MVL Service And Maintenance Manual

6.12 MAIN POWER CIRCUIT TROUBLESHOOTING

Machine Will Not Power Up

Check For These Obvious Conditions First:
• Battery voltage is 24 volts. (Sufficient Charge in Batteries to Operate Machine)
• Positive (+) and negative (–) battery cable connections clean and tight at both the Batteries and the Ground Control Module lugs.
• Main Power Selector Switch (key) positioned to either Platform or Ground Control Mode.
• Emergency stop buttons on both the Ground Control Module and the Platform Control Console in the RESET position (out).
STEP
1. Check for 24V DC at the positive (+) and negative (–) main power
cable connections on the Ground Control Module.
2. Check continuity of the Emergency Stop wires running to the Plat-
form Control Console, pins-10 and 1 on the P4 connector at the
Ground Control Module.
3. Remove the 9-pin Platform Control Console connector at the Plat-
form Junction Box and check continuity between pins-1 and 2 to the
Emergency Stop Switch in the Platform Control Console cable.
4. Check continuity of the wires running from the P4 connector on
Ground Control Module to the Platform Junction Box;
P4 connector, Pin-1 to Junction Box Pin-2 and
P4 connector, Pin-10 to Junction Box Pin-1
31215825
Table 6-41. Machine Will Not Power UP
ACTION
SECTION 6 - TROUBLESHOOTING
SPEC YES
24V DC Go to Step 2
Replace the
— Ground Control
Module
— Go to Step 4
Replace Platform
—
Control Console
NO
Replace the 175
Amp Inline Fuse
on the Positive
power cable
Go to Step 3
Replace the
Platform Control
Console
Repair or Replace
Wiring
6-37