KFAS: Fanuc CNC Parts, Service, & Repair

K Factory Automation Services has large inventory of Fanuc parts in stock and we maintain a full service in-house repair facility.

When the status LEDs on Alpha i-B amplifiers are not lit (Fanuc Manual B-65285EN)

LEDs Do Not Light up.
(1) Meaning
24 VDC voltage (CXA2D) for the control power supply is not supplied.
Or, 24 VDC voltage is short-circuited.
(2) Cause and troubleshooting
(a) If the 7-segment LED lights up when you remove the cable from connector CXA2A and turn
on the control power supply (24 VDC), the 24 VDC power supply of a servo or spindle
amplifier may be short-circuited.
→ Detect the amplifier which causes the power to be short-circuited by sequentially connecting
the cable from the Power Supply and replace it.
(b) If the 7-segment LED does not light up when you remove the cable from the connector CXA2A
and turn on the control power supply (24 VDC), the Power Supply may be damaged.
→ Replace the Power Supply.