Cause : GROUND Phase comes when the ground fault test, a current flows in a phase in which no valve has been triggered or the UCE monitoring has responded in the phase in which the valve has been triggered.

1. Read-out the fault value from R949.
2. The digit of the xth position indicates the valve, where the fault occured at power-up.
3. The digit of the xth position defines the phase, in which I f is 0, and thus a valve is defective (always conductive).
4. Check the phase assembly for defective valves (always conductive).