This error is caused when the drive sees more than 20 indexer pulses within the first second after a DRIVE1 is commanded, or power is cycled to the drive. This error only applies to drives running in DMODE 6, 7, 8, or 9(position mode) and will never enable otherwise.
When a DRIVE1 command is issued, the drive cannot enable instantaneously. If the GV/GT sees more than 20 pulses from the controller (before the drive has had a chance to physically enable, the bit will go active, but will not necessarily shut down the drive.
Place a time delay in the program after the DRIVE1 command to allow the GV/GT to energize. Additionally, the FLTSTP command can be used to disable this indexer pulse-checking mode.