Epson Stylus 820 Service Manual page 86

Stylus Color IIs / Stylus 820
5.1 OVERVIEW
This section describes troubleshooting at the unit level and for abnormal printing(missing-aligned dots). The
EPSON Stylus Color IIs/Stylus 820 uses a new print head that is different than the previous Stylus Color print
head. Because of its designs, indicating that the cartridge is low or out of ink. If you remove or even partially
remove a cartridge unit before it is out of ink, air invades the print head nozzle(s) and the ink cartridge. Once
air bubbles clog the nozzle(s), they are very difficult to eliminate. Refer to Section 5.5 to attempt to clear
clogged nozzle(s).
The ink out sensor on the printer is monitoed by the firmweare counter. If you replace an ink
cartridge before it ink sensor is activated, you must clear the EEPROM first.
Electric Circuit
Repair (Section 5.1.1)
Power Supply Board
Repair (Section 5.1.1.2)
Control Board Repair
Figure 5-1. Trouble Shooting Construction
Motor
CR Motor
PF Motor
Rev. A
Caution
START
M-4C10 Mechanism
Repair (Section 5.1.2)
(Section 5.1.1.2)
END
Table 5-1. Motor Resistances
Resistance Range
22 Ω ± 7%
21 Ω ± 1 Ω
Dot-missing Repair
(Section 5.1.3)
I/C Repair
(Section 5.1.3.1)
Tool Repair
(Section 5.1.3.2)
Temperature
At 25 °C (77 °F)
At 25 °C (77 °F)
Troubleshooting
5-1