IBM 4247 Maintenance Information page 245

9 Wire Printhead
Pin 1
Ribbon Lift
Connector
26 Pin
Connector
Figure 26. 9-Wire Printhead Wiring (Model 002)
RESISTANCE MEASUREMENTS
Note: Allow the printhead to cool before taking resistance measurements.
Table 32. 9-Wire Printhead Resistance Measurements
Part
Print Wire Coil
Thermal Sensor
Example: To measure the resistance of the coil for print wire 1, measure between pins 21 and 22 of the 26-pin
cable connector.
Not
Used
Pin 1
Resistance
5 Ohm ±10%
1000 Ohm ±6%
Temperature
20°C (68°F)
25°C (77°F)
Chapter 3. Circuit Diagrams
245