Troubleshooting Guide for Inkjet Batch Coding Machines

March 25, 2025

Sometimes, production comes to a frustrating halt. Not because a shipment is late, but because everything seems fine—until the batch code is smudged, unreadable, or missing. Suddenly, all attention is on the inkjet coder.

Batch coding machines are crucial. They’re the final step before a product is ready to go. If they fail, the entire production line can slow down or stop completely.

This guide isn’t full of complicated theory—it’s based on real experience in water plants, soft drink factories, and industries where every second matters. If you’ve ever been stuck with a stalled production line, trying to fix an error or clean a clogged nozzle, this guide is for you.

The First Layer: Most Common Inkjet Coding Problems

1. Missing Characters or Incomplete Codes

When characters drop out or entire codes vanish mid-print, the cause is often straightforward—clogged nozzles or ink delivery issues. In an automatic batch coding machine, this is a red flag for print quality breakdown.

Likely Causes:

• Clogged or dried ink nozzles
• Low ink or solvent levels
• Incorrect printhead distance from product
• Faulty cables or driver circuitry
• Excessive product speed
• Encoder malfunction

Troubleshooting Checklist:

1. Confirm ink and solvent levels are sufficient and fresh.
2. Run the purge/cleaning cycle—multiple times if needed.
3. If issue persists, do a manual cleaning of the printhead.
4. Measure and adjust the printhead distance as per the manual.
5. Power down and inspect all electrical connections.
6. Examine encoder and conveyor speed for inconsistencies.

Insight: Most incomplete codes stem from something affecting ink flow—delivery, distance, or electronics.

2. Faded or Light Prints

This is where you know something’s wrong, but it hasn’t yet caused rejection. The print is legible—but barely. This issue often plagues batch printing machines operating in varying temperatures or with aging ink.

Possible Reasons:

• Low or expired ink
• Improper ink-to-solvent ratio
• Excessive distance from printhead to product
• Partial nozzle blockages
• Incorrect voltage or drop size settings

Steps to Resolve:

1. Refill ink and confirm it’s within expiration.
2. Recheck the ink/solvent mix ratio if your model allows it.
3. Readjust the printhead distance (if too far, ink dries mid-air).
4. Run purge and manual cleaning routines.
5. Access print settings—try increasing drop size or voltage slightly.

Insight: Faded codes generally reflect weak ink impact—either from degraded ink or reduced control over jetting parameters.

3. Smudged or Blurry Prints

This issue is tricky—especially in high-speed auto batch coding systems. One bottle prints well, the next smears the date across the label. The cause often lies in drying time and product movement.

Common Triggers:

• Printhead positioned too close
• Excess ink being jetted
• Irregular or high-speed product movement
• Static interference
• Ink/product incompatibility
• Damp product surfaces

Fixing the Issue:

1. Recalibrate the printhead to create a bit more distance.
2. Adjust ink density or reduce drop size.
3. Check and stabilize conveyor speed and product guides.
4. Ensure the machine and line are grounded to reduce static.
5. Reconfirm ink compatibility with your product material.
6. Only print on completely dry surfaces.

Insight: Smudges usually indicate ink isn’t drying quickly enough—or is being spread by erratic product movement.

4. Ink Leaks

Leaks aren’t just messy—they’re a maintenance nightmare. Left unchecked, they can affect sensors, electronics, and surrounding equipment. In manual batch coding machines, leaks usually come from physical wear and loose fittings.

Typical Causes:

• Damaged or old tubing
• Loose connectors or joints
• Faulty seals
• Overfilled reservoirs
• Damaged printhead casing

Action Plan:

1. Power off the machine for safety.
2. Visually inspect tubing, connectors, and reservoirs.
3. Tighten fittings—gently. Don’t overtighten.
4. Replace any worn tubing or damaged seals.
5. Never overfill the reservoir—follow the fill-line markers.
6. Inspect the printhead casing for cracks.

Insight: Even small leaks can disrupt print quality and create long-term damage. Quick attention is critical.

5. Error Codes and System Alerts

At first, error codes seem like nuisances—but they’re actually your coder’s best communication tool. Every automatic batch coding & printing machine displays fault codes for a reason.

Root Issues:

• Low fluid levels
• Sensor errors
• Internal communication breakdowns
• Component faults

What to Do:

1. Record the error code exactly as shown.
2. Refer to the machine’s manual for its meaning.
3. Follow the exact steps outlined by the manufacturer.
4. If unresolved, contact technical support.

Insight: Never ignore or guess an error code. It’s often the earliest sign of a much bigger issue.

Uncommon, But Critical Issues in Batch Coding Machines

Printhead Failure

In high-volume production, a printhead can overheat, short-circuit, or wear out. If you’ve ruled out nozzle clogs and ink levels, a failing printhead may be the culprit.

Troubleshooting Path:

1. Check power supply and voltage regulation.
2. Confirm secure electrical connections.
3. If print distortion or total failure continues, prepare for printhead replacement—only after consulting the manual.

This failure is more common in older mineral water equipment or under poor maintenance conditions.

Pump Failure

In coders with internal pumps, failure leads to ink starvation.

Causes and Symptoms:

• Motor burnout
• Worn diaphragm or blockage
• No ink flow despite full reservoir

Fix Steps:

1. Check power delivery to the pump.
2. Listen for motor operation during printing.
3. If silent, disassemble pump assembly and inspect parts.
4. Replace pump if diagnosed as faulty.

Pump issues are rare but can occur in high-volume mineral water manufacturing environments.

Predictive Troubleshooting: Stay Ahead Before It Fails

Success isn’t just in fixing issues fast—it’s in spotting them before they even surface.

• Data Logging: Record error codes, print anomalies, and adjustments regularly.
• Trend Review: Spotting gradual shifts—like increasing ink use or more frequent purging—can highlight deeper issues.
• Operator Training: Ensure every shift understands the basics—troubleshooting is a team responsibility, not just a technician’s job.

When used proactively, batch printing machines become smarter with you.

Final Thoughts: Proactive Troubleshooting Builds Resilience

Troubleshooting inkjet coders is about developing a systematic mindset. First, isolate the symptom. Then, address causes one by one. Whether it’s a blurry print on a bottle or a code that never appeared, the solution always lies in your ability to act fast—and act smart.

Every production floor in the mineral water plant business faces issues. The difference between panic and performance is preparation.

Partner with Experts Who Understand Your Process

At DTPPL, we don’t just provide machines—we support them. As a trusted manufacturer and supplier of batch coding machines, we’ve helped hundreds of teams reduce downtime, increase reliability, and become confident troubleshooters.

Don’t let minor issues become major stoppages. Get in touch with DTPPL to upgrade your batch coding confidence.