Why does the print head of a dot matrix printer not move when I turn on the power? Normally, the print head does not move back and forth a few times. Now the light is on and the print head cannot move

Why does the print head of a dot matrix printer not move when I turn on the power? Normally, the print head does not move back and forth a few times. Now the light is on and the print head cannot move.

In this case, the ribbon is generally faulty:

1. The drive belt of the ribbon driving wheel is worn or broken

This fault is caused by the drive belt Caused by prolonged use or friction of the character chain with the drive belt. The solution is to adjust the position of the character chain so that it no longer rubs the drive belt; if it is broken, please replace it.

2. The ribbon movement sensor signal is interrupted

First check whether the ribbon movement sensor signal line is damaged. If it is broken, please replace the signal line; then check the interlock conversion board Check whether the ribbon motion sensing signal line at the upper J6 socket is damaged or has poor contact. Please replace or plug in the signal line.

3. Hall effector is damaged

If the ribbon is frequently stuck, the Hall effector is constantly squeezed, causing damage and breakage. This kind of failure can only replace the ribbon rotating arm assembly or replace it with a ribbon motion sensor.

4. The ribbon is stuck

The edge of the ribbon is detached and fuzzed, and it is easy to get entangled in the ribbon wheel, causing the ribbon wheel to be stuck and the ribbon cannot retract normally. Comes with box. The solution is: first open the printer cover, open the interlocking handle of the ribbon rotating arm and the hammer row, gently pull the ribbon back at the feeding end of the ribbon box, and then close the ribbon rotating arm and the hammer row interlocking handle, turn on the power, and the ribbon will be put back into the ribbon box after the machine performs self-test.

Extended information:

Methods to solve dot matrix printer problems:

1. First check whether the power circuit board and the motherboard are connected correctly (whether the cable is plugged in) Reverse or angled connection or virtual connection), if the connection between the power circuit board and the motherboard is poor, re-plug the connection.

2. If the connection between the power circuit board and the motherboard is normal, then check whether the connection between the motherboard and the control panel is normal. If not, reconnect the connection.

3. If the connection between the motherboard and the control panel is normal, then check whether the power switch is normal. If the power switch is damaged, replace the power switch.

4. If the power switch is normal, then disconnect the power circuit board from the motherboard, then connect to 220V, and use a multimeter to check whether the DC output voltage of the power circuit board is normal (generally 5V and 42V for printers) .

5. If the output voltage of the power circuit board is abnormal, the power circuit board is damaged. Check whether the power circuit board switch is damaged. If it is damaged, replace the power circuit board switch.

6. If the switch of the power circuit board is normal, then check whether the fuse F1 of the primary circuit in the power circuit board is blown. If fuse F1 is blown, check whether there is a short circuit in the other circuits on the power circuit board. If not, replace F1.

7. If the fuse is normal, then check whether the switch tube, diode, rectifier bridge circuit, etc. in the power circuit board are normal. If not, replace the damaged components or power circuit board.

8. If the power output voltage measured in step 4 is normal, then unplug the motor connection, header cable, and sensor cable from the motherboard, and only connect the power circuit board cable and control panel cable. . Then turn on the power and see if the power indicator light on the control panel is on.

9. If the power indicator light on the control panel shows that there is power, it means that the motherboard is normal and the problem lies in the peripheral electrical components.

10. Then check whether the carriage motor and paper feeding motor are burned out. If they are burned out, replace the damaged motor.

11. If the carriage motor and paper feed motor are normal, then check whether the print head cable is normal (whether there is any short circuit caused by wear, disconnection, etc.). If it is not normal, replace the print head cable.

12. If the print head cable is normal, then remove the print head, then power on the printer to see if there is a display. If the printer has power, it means there is a short circuit inside the print head (short circuit in the print head coil, needle drive tube or chip 2B). Replace the short-circuited parts or replace the print head.

13. If the fault persists after removing the print head, then check the sensor and replace the short-circuited sensor.

14. If the indicator light on the printer control panel does not display in step 8, then check whether the chip in the motherboard has any signs of burnt out (such as cracking, heat, etc.). If so, check for abnormalities. chip, if the chip is damaged, replace the chip.

15. If there is no burned chip, then measure the resistance of the 5V power supply on the motherboard to ground to determine whether the motherboard is short-circuited. If the motherboard is shorted, repair or replace the motherboard.

16. If the motherboard is not short-circuited, then check whether the gate array circuit, CPU and other components in the motherboard are damaged. If damaged, replace the damaged component.

17. If there are no damaged components in the motherboard, finally replace the motherboard.

Baidu Encyclopedia-Dot matrix printer