Overview - Epson Stylus PHOTO 820 Service Manual

EPSON Stylus PHOTO 810/820

3.1 Overview

This chapter describes how to identify troubles in two levels: unit level repair and
component level repair. Refer to the flowchart in this chapter to identify the defective
unit and perform component level repair if necessary. This chapter also explains motor
coil resistance, sensor specification and error indication.
START
Unit level troubleshooting
Unit repair
Assemble & Adjustment
Figure 3-1. Troubleshooting flowchart
Troubleshooting
END
Table 3-1. Motor, coil resistance
Motor Location
CR motor
PF motor
Table 3-2. Sensor check point
Sensor name Check point
HP/PE Sensor CN4/Pin 1 and 2
Thermistor
TH1 (on the Head
driver board)
(THM)
Overview
Check point
Pin 1 and 3
7.8 Ohms 10%
CN12
(at 25 C/ phase)
Pin 2 and 4
Pin 1 and 3
6.0 Ohms 10%
CN7
(at 25 C/ phase)
Pin 2 and 4
Signal level
Off
• Out of CR home
Less than 0.7V
position
• No paper
On
• Within CR home
More than 2.4V
position
• Detect the paper
Analog signal 10 K (at 25 C)
Revision A
Resistance
Switch mode
52