Removal and replacement of ADU modules
8-28 Chapter 8: Service & maintenance 99-145912-A
8.6.4 To replace the DC-Motor Driver Module
(DDM)
The ADU is equipped with three (3) DDMs for the axes:
• Cross Elevation DDM
•Elevation DDM
• Azimuth DDM
By the input from the PCM the DDM controls the power delivered to
the DC-motors to control the orientation of the ADU.
The DDM has two LEDs for status and troubleshooting:
•Power LED: green or Off
• Service LED: green or red
Figure 8-26: VIM2 module for Ka antenna
After installing a new VIM you must update the calibration
data. For instructions see To update VIM2/PCM
calibration data on page 8-67.