This bit activates when the Gemini drive has detected an invalid parameter value which has been downloaded to the Gemini unit. This can be caused by a parameter value that has been set outside of the factory-specified range, a parameter that has been set to an illegal null (or zero) value, or a required parameter value has not been set.
Query the error using the TCS command. The TCS code will describe which parameter setting(s) has triggered the error. Change or correct the parameter value as needed.