Common Barcode Scanner Problems and How to Troubleshoot Them

A barcode scanner that stops reading, types gibberish, or drops the Enter after every scan brings the checkout to a halt fast. The good news is that the vast majority of scanner problems are configuration or connection issues you can fix yourself in a couple of minutes, not hardware faults. This guide covers the real causes in the order you should check them, for USB, wireless and 2D barcode scanners.

Start here: is it the scanner, the connection, or the settings?

Most "broken scanner" calls are not broken scanners. Before anything else, do a quick test: open a blank Notepad or text document, click into it so the cursor is flashing, and scan a known-good barcode. What happens next tells you where the problem is:

• Nothing appears at all = connection or power issue, or the cursor was not in an active field.
• Wrong or extra characters appear = keyboard layout or configuration issue.
• The data appears but runs together with the next scan = the Enter/suffix is not set.
• It reads in Notepad but not in your POS = the problem is your POS software setting, not the scanner.

Scanner will not scan anything

• Check the cursor is in an active field. A keyboard-wedge scanner types wherever the cursor is. If no field is selected, the scan goes nowhere. Click into the field first.
• Check the connection. For a USB scanner, reseat the cable and try a different USB port. For a wireless scanner, confirm it is paired and in range, and that the base or dongle is connected. See our cordless barcode scanners if you are setting one up fresh.
• Confirm it has power. Most scanners beep and flash when powered. No light usually means no power: check the cable, the battery on a wireless model, or the charging cradle.
• Listen for the beep. If the scanner beeps when you scan but nothing reaches the screen, it is reading fine and the issue is the connection mode or software, not the scan itself (see the next two sections).

Scanner reads, but the wrong characters appear

If a scan produces strange symbols, swapped characters, or numbers where letters should be, the scanner's keyboard layout does not match your computer. Scanners default to a US keyboard layout, and a mismatch with an Australian or other regional layout produces wrong characters. The fix is to set the scanner to the correct country/keyboard layout, which is done by scanning a configuration barcode from the scanner's manual. This is one of the most common and most misdiagnosed scanner issues.

No Enter or line break after each scan

If every scan lands on the same line and runs into the next, the scanner is not sending an Enter (carriage return) after the data. Most POS systems expect that Enter to submit the item. The fix is to configure a suffix: scan the "add carriage return / Enter suffix" configuration barcode from the manual. Many scanners ship without a suffix set, so this is a normal first-time setup step rather than a fault.

Barcode not recognised, or it won't read a QR code

• Symbology disabled. Scanners read specific barcode types (symbologies) such as EAN, UPC, Code 128 or QR, and some are switched off by default. If one type of barcode reads and another does not, the symbology is probably disabled. Enable it by scanning the relevant configuration barcode from the manual.
• 1D scanner cannot read 2D codes. A 1D laser scanner physically cannot read a QR code or DataMatrix. If you need to read QR codes or codes on a phone screen, you need a 2D barcode scanner, not a 1D laser model.
• Damaged or low-quality barcode. Check the barcode itself for smudges, creases or poor print quality, and try a different copy. Clean the scanner window with a soft cloth, and check the distance and angle, as every scanner has a working range.

It reads in Notepad but not in my POS

If the scanner types correctly into a text document but does nothing in your point of sale, the scanner is fine and the issue is in the software. Check that the scan field in the POS is focused, that the POS is set up to accept scanner (keyboard) input, and that any required prefix or suffix matches what your POS expects. Some POS systems need the scanner in keyboard-wedge (HID) mode rather than a serial or SDK mode, which again is set with a configuration barcode.

Wireless and Bluetooth scanner problems

• Pairing. Re-pair the scanner with its base or device. For Bluetooth models, remove the old pairing and pair again from scratch.
• Range and interference. Cordless scanners have a working range, and nearby Wi-Fi routers or other electronics can interfere. Move closer to the base and away from interference to test.
• Battery. Charge or replace the battery and make sure the cradle is powered.
• iPad and tablet pairing. For an iPad or tablet till, use an MFi-certified or HID-mode Bluetooth scanner. If the on-screen keyboard keeps disappearing while the scanner is connected, there is usually a button or configuration to toggle the on-screen keyboard back on. See our phone and tablet compatible scanners for models built for this.

When to repair or replace

Cables and batteries are cheap and worth replacing. But if a scanner is misreading constantly after cleaning and reconfiguration, or the trigger and internals are worn from heavy use, replacement is usually the better call. Match the new scanner to the job: a handheld scanner for a retail counter, a cordless model for moving around stock, or an industrial scanner for a warehouse. Browse the full barcode scanner range or call us for help choosing.

A quick setup checklist for a new scanner

Most first-time scanner issues are solved by three configuration barcodes from the manual: set the correct keyboard/country layout, add an Enter (carriage return) suffix, and enable the barcode symbologies you use. Do those three and test in Notepad before connecting to your POS, and most problems never appear.

Frequently asked questions

Why is my barcode scanner not scanning anything?
First click into a text field so the cursor is active, then scan. If still nothing, reseat the USB cable or try another port (for wireless, check pairing, range and battery). If the scanner beeps when you scan but nothing appears, it is reading fine and the issue is the connection mode or your software, not the scan.

Why does my barcode scanner type the wrong characters?
The scanner's keyboard layout does not match your computer. Scanners default to a US layout, which produces wrong characters on an Australian setup. Fix it by scanning the configuration barcode in the manual that sets the correct country/keyboard layout.

Why is there no Enter after each scan?
The scanner has no suffix configured. Scan the "add carriage return / Enter suffix" configuration barcode from the manual so each scan submits and moves to the next line. This is a normal setup step, not a fault.

Why won't my scanner read a QR code?
A 1D laser scanner cannot read QR codes or other 2D codes. You need a 2D imager. If your 2D scanner still won't read a particular code, the symbology may be disabled, which you can enable with a configuration barcode.

How do I connect a Bluetooth barcode scanner to an iPad?
Use an MFi-certified or HID-mode Bluetooth scanner, then pair it from the iPad's Bluetooth settings. If the on-screen keyboard disappears while the scanner is connected, toggle it back on (there is usually a button or config barcode for this).

Need a replacement or help choosing? POS Plaza stocks a full range of barcode scanners with local Australian stock and same-day dispatch from Sydney. Call our team on 1300 115 808.