EPSON AcuLaser C1900/AcuLaser C900 Revision B
Troubleshooting Check Points and Remedy for Paper Jam 162
TRANSPORT COMPONENT OF DUPLEX UNIT / INVERSION AND SIDING 
COMPONENT OF DUPLEX UNIT
 Detection Timing
 Solution
 Electric parts which can cause the jam:
• Duplex Unit Transport Sensor (PC17)
• Duplex Unit Control Board (PWB-A)
3.4.4  Checking Method for Electric Parts
At occurrence of a paper jam or any other trouble, you can check the relevant electric 
parts for their normality by the method as described below:
SENSOR
SWITCH
Table 3-10. Detection Timing
Category Explanation
Inversion and siding 
component / 
transport 
component jam
Even on the lapse of a predetermined time, the paper does not 
intercept the light to the duplex unit transport sensor (PC17).
Retaining paper 
detection in 
transport 
component
The light to the duplex unit transport sensor (PC17) is intercepted 
when the main switch is turned on, the door and cover are opened 
and closed or a jam or trouble is cleared.
Table 3-11.
Step Action Refer to
WARNING DIAGRAM
Control Signal
1 Initial checking p.159 -
2 Check the operation of PC17. p.162 PC17_ON
3 Replace the PWB-A. - -
Table 3-12. Checking Method (Sensor) 
Step Check Item
Yes/
No
Solution
1
Does the input signal to Control Board 
change when light to the sensor is 
intercepted? (H → L, L → H)
NO Replace the sensor
YES Replace the Control Board
Table 3-13. Checking Method (Switch) 
Step Check Item
Yes/
No
Solution
1
Does the input signal (NO) to Control Board 
turn L → H when the switch is turned on?
NO Replace the sensor
YES Replace the Control Board
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