Driver Board Failures - Intermec EasyCoder PX4i Service Manual

17.6 Driver Board Failures

EasyCoder PX4i and PX6 Service Manual
Description:
• Some or all of the following functions do not work properly.
- Console
- Printhead
- Platen roller/ribbon rewind stepper motor
- Liner rewind stepper motor
- Cutter
Possible Causes and Suggested Remedies:
• Faulty driver board.
- Check voltages using the test points on the CPU board, see Chapter
15.4. If all voltages are missing, check the 24 VDC output from the
CPU board and the cable between the power supply and the driver
board. If the 24 VDC input to the driver board is OK, the trouble is
likely to be in the driver board.
- Check the 24 VDC to the CPU board on connector P1, pin 1.
- Check the 24 VDC to the printhead on connector P5 while perform-
ing a print operation.
- Check the 33 VDC to the platen roller/ribbon rewinder stepper
motor on connector P10 while performing a feed or print opera-
tion. The stepper motor driver may be damaged because the platen
roller has been manually rotated while power was on, unintentionally
making the stepper motor work as a generator.
- Check the 33 VDC to the platen roller/ribbon rewinder stepper
motor on connector P11 while performing a feed or print operation.
- Check the 24 VDC to the cutter on connector P12 while performing
a cut operation.
If the any of the voltages are missing or are wrong, replace the driver
board without attempting to repair it. The only exception is if you are
positively sure that the fuse F1 has blown because of a short-circuit of
your own doing. In that case, you can cut off the legs of the fuse and
solder a new 4A fuse in its place.
Chapter 17 — Troubleshooting
219