I would run DMCTerminal and see if it works with native commands, the voltage should be 0v not 3.8 at power up. Make sure the 100 pin cable is pushed right in both ends as this has been known to cause open ground return.
Make sure you are set up for analog and not steppers with the board jumpers and also interogate using the MT command to see what type of motors are set up in the card.
To test the analog output, disconnect it from the drive and then use OF commands to set various output voltages (verify with TT) and then physically measure with a DMM. You should have a full range of roughly +/-10v. If these voltages differ, then the possibly failure could be with the analog buffer switch (ADG202AKN or MAX332 chip) located at U1 on the ICM unit. You should also make sure that TL is set to 9.9982
Set TL Z to zero should zero the analog out for Z.
Other commands that should null the analog out is SH (Servo Here) MO (motor off) and RS (reset).
Make sure you are using the main board GND and not ISO ground for the command.
I would also zero the KD,KP and KI commands for that axis.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.