When a CIJ printer stops printing, production stops with it. The good news: the majority of faults fall into ten predictable categories, and most can be resolved on the line within minutes.
Use the table below as a first-response guide. Always follow your manufacturer’s safety instructions and never open the ink system while the printer is pressurized.
Fault 1: No print at all
| Possible cause |
What to check |
Fix |
| No trigger signal |
Photocell, encoder or PLC input |
Realign or replace the sensor; check the trigger LED |
| Message deleted or not selected |
Message library |
Reload the correct message |
| Printhead too far from the product |
Printhead distance |
Reset the gap to the specified distance |
| Printer in fault/standby |
Alarm screen |
Clear the fault and restart the jet |
Fault 2: Missing dots or gaps in characters
| Possible cause |
What to check |
Fix |
| Partially blocked nozzle |
Print quality test |
Clean the printhead using the approved procedure |
| Ink contamination |
Ink batch and filter age |
Replace the filter; if repeated, flush the system |
| Low ink pressure |
Pressure reading |
Investigate pump and filter condition |
Fault 3: Unstable or broken ink stream
| Possible cause |
What to check |
Fix |
| Air in the ink system |
Recent maintenance or ink change |
Run the purge or bleed procedure |
| Nozzle wear |
Nozzle condition after cleaning |
Replace the nozzle |
| Viscosity out of range |
Viscosity reading |
Adjust solvent addition; check the viscosity sensor |
Fault 4: Viscosity alarm
| Possible cause |
What to check |
Fix |
| Solvent level low |
Solvent container |
Top up and confirm the alarm clears |
| Viscosity sensor drift |
Calibration date |
Recalibrate or replace the sensor |
| High ambient temperature |
Room conditions |
Stabilize temperature and monitor consumption |
Fault 5: Pressure alarm
| Possible cause |
What to check |
Fix |
| Clogged filter |
Filter hours and pressure trend |
Replace the filter |
| Pump wear |
Pump output and noise |
Service or replace the pump |
| Blocked or kinked tubing |
Visual inspection |
Clear or replace the tubing |
Fault 6: Poor print quality at high speed
| Possible cause |
What to check |
Fix |
| Line speed exceeds print capability |
Speed vs message length |
Reduce speed, shorten the message, or change the technology |
| Incorrect encoder ratio |
Encoder settings |
Recalculate and update the parameters |
| Product slipping on the conveyor |
Mechanical handling |
Stabilize product spacing and guidance |
Fault 7: Codes printed in the wrong position
| Possible cause |
What to check |
Fix |
| Trigger delay mis-set |
Delay value |
Adjust delay using a printed test sample |
| Sensor detecting the wrong edge |
Sensor position |
Re-align and confirm detection on the product |
| Varying product gaps |
Conveyor behavior |
Use encoder-based triggering or add product detection |
Fault 8: Ink leakage
| Possible cause |
What to check |
Fix |
| Loose fitting or worn seal |
Connections and seals |
Tighten or replace the seal — do not overtighten |
| Damaged tubing |
Tubing inside the cabinet |
Replace the affected section |
| Overfilled ink container |
Ink level |
Correct the level and clean the area |
Fault 9: Print rubs off or fades
| Possible cause |
What to check |
Fix |
| Ink not matched to substrate |
Surface energy and ink type |
Switch to the correct ink family |
| Insufficient drying time |
Conveyor length and airflow |
Increase dwell time or adjust ventilation |
| Surface contamination |
Oil, dust or condensation |
Clean or pretreat the surface |
Fault 10: Printer shuts down unexpectedly
| Possible cause |
What to check |
Fix |
| Power fluctuation |
Supply voltage and grounding |
Stabilize the supply; check the UPS |
| Overheating |
Cabinet fan and vents |
Clean vents and confirm airflow |
| Safety interlock triggered |
Cabinet doors and guards |
Close and reset the interlock |
When to stop troubleshooting and call service
Escalate to a qualified technician if you see ink leaking inside the cabinet, repeated pressure or viscosity faults after correct maintenance, burned electrical smells, or error codes that return immediately after reset.
Preventing repeat faults
- Keep the daily checks short but consistent.
- Record every alarm with time and production context.
- Replace filters on schedule, not when they fail.
- Keep critical spares on site.
- Review faults monthly to find patterns — repeated nozzle clogging usually points to an ink, filtration or shutdown-procedure issue.
Frequently asked questions
Why does my printer print perfectly and then throw a fault? Intermittent faults usually trace back to sensors, connectors or temperature. Check the alarm history and when the fault appears in the production cycle.
Can I reset an alarm without fixing the cause? You can, but the fault will return — often at the worst possible moment. Use the log to find the root cause.
How often should nozzles be replaced? It depends on ink, filtration and runtime. Track print quality trends and replace when cleaning no longer restores a stable stream.
A faster path to reliable coding
Most of these faults disappear with correct daily maintenance, the right ink and a proper shutdown procedure. WDOTMARK supports manufacturers with CIJ printers, genuine consumables, spare parts and technical service. Send us your fault log or error message and we will help you diagnose the root cause.
Ask WDOTMARK for a remote troubleshooting check.
