The RCU is not communicating with the MP. Possible causes are:
The RCU is present but cannot run because of a power-up diagnostic error.
The RCU is not receiving power.
The RCU is not plugged into the MP properly.
For more information, see "RCU Error Codes".
What you should do:
To clear the error, power the MP down.
Check the power cord to the RCU to make sure it is receiving power.
Make sure the cable from the RCU is connected properly to the MP.
Power the MP back up.
If the error reoccurs, contact your Giddings & Lewis service representative.