Hitachi HT-4139-28, Maintenance Manual

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REV0 10.02.15
-H8-37-
■
Replacing the Prism (PC21 Sensor), the PC 22 ASSY (PC22 Sensor), the Prism (PC31 Sensor)
Tools Needed: Magnetic Philips Screwdriver (No.2)
①
Remove the Main Cover, the Side Cover, and the Back Cover. For instructions, please refer to “8.1
Preparation” for instruction
②
Remove the Guide (Lower Mirror), the Cover Sheet. For instructions, please refer to “8.3.13 Replacing the
Lower Mirror ASSY”
③
Unscrew 6 bind-head screws on the Upper Guide and remove the Upper Guide.
Upper Guide ASSY
Bind head screw
Bind head screw
Bind head screw
Bind head screw
Bind head screw
Bind head screw
④
Remove the Sensor
- Unscrew 1 hexagonal screw on the Prism (PC21 Sensor), and remove the Prism (PC21 Sensor)
- Disconnect the connector on PC22 ASSY (PC22 Sensor) from the middle connector. Unscrew 1 countersunk
screw from the Upper Guide ASSY, and remove the PC22 ASSY (PC22 Connector)
- Unscrew 1 hexagonal screw on the Prism (PC31 Sensor) and remove the Prism
⑤
Attach the new Sensor
⑥
Take the reverse steps to attach the Sensor
⑦
After replacing the part, run Auto Calibration Test
hexagonal screw
countersunk screw
#57 Purism
（PC21）
#34 PC22_ASSY
（PC22）
#57 Purism
（PC31）
#34 PC22_ASSY
（PC22）
hexagonal screw
Caution: When removing the Upper Guide ASSY, disconnect the cable connector on PC22 and unlock
the locking wire saddle.