Minolta DI450, Service Manual, Page: 192 / 271

T-1
1. INTRODUCTION
1-1. Reading the Text
1. The paper transport failure troubleshooting procedures are given according to the
symptom. First identify the location where the paper is present and start the procedure
for that particular location. For malfunction troubleshooting, start with step 1 and
onward.
2. Make checks in the numerical order of steps and, if an item is checked okay, go to the
next step.
2. I/O CHECK
2-1. Controlled Parts Check Procedure
To allow the Tech. Rep. to easily and safely determine whether a particular controlled part
is fully operational, this copier provides the following provision. Checking the data of the
input port of the board IC with the copier in the standby state (including a misfeed, malfunc-
tion, and closure failure condition) allows the Tech. Rep. to determine whether signals are
properly input to a controlled part.
<Procedure>
1. When a misfeed or malfunction occurs, locate on a circuit diagram accompanying the
text the controlled part which is probably defective.
2. Select “I/O Check” from the Tech. Rep. Mode menu screen and access the screen that
contains the controlled part picked out in step 1 above. (See SWITCHES ON PWBs/
TECH. REP. MODE.)
3. Check the input port data to determine if a signal is properly input to the controlled part.
<Controlled Part Check Procedure Through Checking Input Port Data>
Example
When a paper misfeed occurs in the paper take-up section of the copier, the Synchronizing
Roller Sensor (PC1) is considered to be responsible for it.
<Procedure>
1. Remove the sheet of paper misfed.
2. From the I/O Check list, it is found that the signal input to PC1 is “Timing Roller.”
3. Select “Tech. Rep. Mode”
→
“I/O Check”
→
“Printer.” Then access the screen that con-
tains “Timing Roller.”
4. Check that the input port data of “Timing Roller” is “0” (sensor is blocked).
5. Move the PC1 actuator to unblock the sensor.
6. Check at this time that the input port data on the screen changes from “0” to “1.”
1: PC1 is operational. 0: PC1 is faulty.
Pattern 1
Go to step 2 if you answered No.
Step Check Result Action
1 ~ YES ~
2
Pattern 2
Go to step 2 if it checks okay.
Step Check Result Action
1 ~ YES ~
NO ~
2