X20 CP3585 CPU has no R/E, RDY/E, S/E, PLK led signal ( even on boot up no red led signal)

A plc x20 cp3585 is not accessible and usable. This plc has led light for DC (Yellow) , CF (Yellow) and ETH (Green blinking). But no led light showing R/E and RDY/F and S/E and PLK. On boot up/ restart/ reboot no red led shows.

Yes this state of the LEDs is not typical for a steady State.

I am wondering which position this Rotating Switch (Mode Selector) has…
Normaly it should point to RUN with the arrow. → Normal operation.
If behaviour does not change you can try BOOT. → Boot onboard Runtime

As it seems not to be in a cabinet, i think your in development phase. You can try an Offline Install to the CF, to ensure the right Projekt is on the PLC. If the Runtime on the CF is not for this type of PLC it could cause this issue.


I have done as you suggest but no change and PLC is still not usable.

I set the Mode Switch to BOOT and removed the CF card. These are the LEDs. (see Picture) + ETH is blinking.
The PLC is accessible via Ethernet in Automation Studio.

if your PLC behaves different for this configuration, its most likely a hardware issue.

The IP Address is from DHCP


I am afraid, PLC hardware may be damaged. In my PLC anyway no red/yellow led light show at situation. And mostly thank you for your response. Is any software or other way to find out which part of hardware is malfunctioning or damaged.