4 — MAINTENANCE
4-21
Main Controller Troubleshooting
Lower Control Mode
• Up Command Does Not Work
1. Check if the LED “UP CTRL SEL” on the main controller is OFF. If
it’s ON, check the Upper/Lower selector switch and make sure it’s set
to Lower Control.
2. While holding “UP” command switch ON,
a. Check LED labeled “RISING” on the main controller. It
should be ON, indicating the UP command switch is OK. If
the LED is OFF, the UP/DOWN command switch on the
machine or the wiring may be faulty.
b. LED’s labeled “PUMP ON” and “UP ON” should be ON. If
LED “RISING” is ON, but LED’s “PUMP ON” or “UP ON”
are OFF, the main controller may be faulty.
• Down Command Does Not Work
1. Check if the LED “UP CTRL SEL” on the main controller is OFF. If
it’s ON, check the Upper/Lower selector switch and make sure it’s set
to Lower Control.
2. While holding “DOWN” command switch ON,
a. Check LED labeled “LOWERING” on the main controller.
It should be ON, indicating the DOWN command switch is
OK. If the LED is OFF, the UP/DOWN command switch on
the machine or the wiring may be faulty.
b. LED labeled “DOWN ON” should be ON. If LED
“LOWERING” is ON, but LED “DOWN ON” is OFF, the
main controller may be faulty.
