CDX-GT40U, CDX-GT40UW, CDX-GT42UE, CDX-GT44U, CDX-GT45U, CDX-GT47UE - Sony Car Audio Service Manual (repair manual). Page 59

In this set, the LCD driver IC (IC901) on the KEY board has been 
changed in the midway of production.
The following changes are performed by this change.

•  Change of the KEY board (suffi x-21/-22) (Refer to this supplement-2)
•  Change of part No. of the FRONT PANEL OVERALL ASSY 

(Refer to page 44, 52 and 53 on original service manual)

•  Change of part No. of the complete MAIN board 

(Refer to page 43 and 48 on original service manual)

•  Change of part for Ref No. IC501 on the MAIN board 

(Refer to page 50 on original service manual)

In this unit, KEY board has been changed in the midway of production.
Discrimination, printed wiring board, schematic diagram and electrical 
parts list of changed KEY board are described in this supplement-2.
Refer to original service manual and supplement-1 for other information.

Note: When the parts of new front panel and the parts of old main unit are 

combined, this unit does not operate normally.