Sega MINI DELUXE THE HOUSE OF THE DEAD 4 Service Manual page 75

If there appears to be a problem with the gun and adjustment in Test Mode makes no difference,
part of the gun is most likely broken.
Use the following instructions to take the gun apart and replace the broken part.
The exterior casing, comprised of cover L and cover R, must be opened up in order to change
interior parts.
As some internal parts are connected to cover R, work with cover R face down on the working
surface.
FIG. 10 a (Unit Interior)
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