The temperature in the MP electronics enclosure is too high.
What you should do:
To clear the error, click Clear error in the XYZ Display window.
To clear it using an RCU-II, press and hold down the Servo Power Off button and then press the Joy button twice.
If the error immediately reoccurs, turn the power to the MP off and allow it to cool down before turning it back on.
If the error reoccurs, contact your Giddings & Lewis service representative.