Epson FX-870/1170 User Manual

Page 56

Troubleshooting

[ T E R M I N A L A S S I G N M E N T ]

Note:

The printhead is
upside down in
this illustration.

[WIRE ASSIGNMENT]

Note:

The commons correspond to the following

printhead dot wires:

COM. 2 =

COM. 8 =

COM.

Figure 3-1. Printhead Resistance

Table 3-4. Printhead Test Points and Coil Resistance

Test Method

Common

Connector

(Set Meter to Ohms. Disconnect

Connector

Pin

Test Pin

Printhead and Check it with

Number

Numbers

Printer Power Off.)

Meter Reading

Printhead

Place one lead on pin 2 and the other on

test pins

and 5 to check the

(at

resistance of printhead dots

and

25” C)

and 13

Place one lead on pin 8 and the other on

test

pins

4, 6, and 13 to check the

Thermistor

resistance of printhead dots

and

and 12 Place one lead on pin 14 and the other lead

on each of the test pins 10, 11, and 12 to
check the resistance of printhead dots

and

Place one lead on each pin.

Approx. 9.3 K

E p s o n

3-3