Hello, Need help !

On Acramatic 850 display, after axis algnament I have an error (00327 X axis open loop).
The resolvers look OK. Could be +/- 15 V ?
On the axis Drive Board I don't have the LED +/- 15V ON.
After the axis alignament, after 5-10 seconds, the error apears and on display X & Z axis position info is changed.
Normal positions are:
X = 4.2000
Z = 10.000

At error:
X = 4.0683
Z = 9.8362 without axis moving
and this situation is permenent after each start up.
The start up diagnosis is correct each time.

Any info will be appreciated,
Marius Borza