somatom AR star Error

I can check error on Monday and will give you an advice...anyway it is not looking good since it looks like filament current problem...

DETAILED DESCRIPTION:
---------------------
Basic filament current is less than 4.2A for more than 8 seconds. This error
could be caused by a broken filament/filament transformer in the Rotanx, faulty
feedback or a too low supply to the filament.

Reason for error:
-----------------
- Fuse F11 on DC2 board (D21).
- ROTANX defective.
- FILAMENT BOARD D24 defective.
- Filament measuring circuit defective.
- CONTROL BOARD D27 defective.
- Check for overheated connectors (X219, X251)

What to do?
-----------
1:
- Check voltages coming from DC1, DC2, (see ACS_Manual, XRS- measurement points).
- Check +40V (+/-0.1V) on filament board D24. Adjustable with R22 on DC1
board
- Replace FILAMENT BOARD D24.
- Check fuse F11 (40V) on DC2 board D21.
2:
- Check cable W305 between DC2 board D21 and FILAMENT BOARD D24, X200 - X211.
- Check cable W314 between CONTROL BOARD D27 and FILAMENT BOARD D24, X234 - 235.
- Check cable W214 between FILAMENT BOARD D24 and ROTANX, X219 - X217.
3:
Measure PULSE_A_FIL (testpoint A) and PULSE_B_FIL (testpoint B) on the
FILAMENT BOARD D24. Replace the CONTROL BOARD D27 if one or both signals are
missing.
4:
- Measure resistance between FILAMENT BOARD D24 and ROTANX (cable W214 pin 1
and 3).
- If the resistance is around 0 Ohms replace CONTROL BOARD D27.
- If the resistance is in the Meg-Ohm range replace the ROTANX.
- If the filament voltage is a stable trapezoidal waveform (around 40Vpp and
180 deg. phase shifted) replace the ROTANX.

I send you the error detail
I'm Siemens CT MRI Service engineer
if you need any help my email
tiseerissa1980@gmail.com
tiseer_issa@yahoo.com