JVC KW-XC939 Service Manual page 38

Information for using a car audio service jig
(1) We're advancing efforts to make our extension cords common for all car audio products.
Please use this type of extension cord as follows.
(2) As a U-shape type top cover is employed, this type of extension cord is needed to check operation of the mechanism assembly
after disassembly.
(3) Extension cord : EXTSH002-22P ( 22 pin extension cord ) For connection between mechanism assembly and main board.
(4) Check for mechanism driving section such as motor, etc.
Disassembly method
(1) Remove the front panel assembly.
(2) Remove the rear bracket.
(3) Remove the heat sink.
(4) Remove the top chassis assembly and bottom chassis assembly.
(5) Remove the main board.
(6) Remove the changer control board.
(7) Reattach the heat sink with two screw E. (Refer to Disassembly method.)
(8) Reattach the front panel assembly with two screws A. (Refer to Disassembly method.)
(9) Confirm that current is being carried by connecting an extension cord jig.
CAUTION :
Be sure to attach a heat sink on the power amplifier IC of a main board when supplying the power.
If voltage is applied without attaching the heat sink, the power amplifier IC will be destroyed by heat.
CD mechanism assembly
Extended cable
EXTSH002-22P
1-38 (No.MA041)
Cassette mechanism assembly
Changer control board
Main board
*The box etc. is used as a stand.