Cash Drawer Failure: Post-Refund Diagnostic and... | terminalfaults.org

Technical Background:

Cash drawers are typically triggered by a solenoid. The card terminal sends a voltage signal (often 12V or 24V DC) via a cable (typically RJ11/RJ12) to activate the solenoid, releasing the drawer latch. Signal attenuation due to cable damage or corrosion can prevent sufficient voltage from reaching the solenoid. Electrostatic discharge (ESD) can also interfere with the signal or damage the interface.

Symptoms:

Cash drawer fails to open following a refund transaction initiated at the card terminal.

Possible Causes:

Insufficient voltage from the card terminal due to a software or hardware issue.
Damaged RJ11/RJ12 cable or connector, causing signal attenuation.
Corrosion or debris on the RJ11/RJ12 connector contacts, impeding signal transmission.
Malfunctioning solenoid within the cash drawer due to mechanical wear or electrical failure.
Software configuration error within the card terminal preventing the open-drawer signal from being sent after a refund.
Electrostatic discharge (ESD) event affecting the electronic components.

Solution:

1

Safe Handling: Unplug the RJ11/RJ12 cable from both the cash drawer and the card terminal.
2

Inspect the RJ11/RJ12 cable for any visible damage (cuts, crimps, or bent pins). Replace if necessary.
3

Examine the RJ11/RJ12 connectors on both the cable and the ports on the cash drawer and card terminal for corrosion or debris. Clean gently with a dry, non-abrasive cloth.
4

Reconnect the RJ11/RJ12 cable, ensuring a secure connection at both ends.
5

Initiate another refund transaction on the card terminal to trigger the cash drawer. Observe if the drawer opens.
6

If the drawer still fails to open, verify the card terminal's software settings to ensure the open-drawer command is enabled for refund transactions. Consult the terminal's user manual.
7

As a test, initiate a 'no-sale' transaction (if available on the terminal). This isolates the 'refund' process. If the drawer opens on a 'no-sale', the issue is likely within the refund software routine.

Safety Warning:

Avoid forcing the cash drawer open, as this could damage the latch mechanism. Do not use excessive force when plugging/unplugging cables. Static electricity can damage electronic components. Ground yourself before touching any connectors or electronic components. NEVER attempt to open any part of the card terminal; this will trigger anti-tamper mechanisms.

Prevention:

Implement cable strain relief to prevent damage to the RJ11/RJ12 cable and connectors. Regularly clean the connectors with a dry, non-abrasive cloth. In dry environments, consider anti-static measures to reduce ESD risk (e.g., anti-static mats).

Expert Tip:

Try a known-good RJ11/RJ12 cable to quickly rule out cable failure. Some cash drawers have a manual release lever located underneath; check if this works as a temporary workaround and confirms a solenoid issue.

Frequently Asked Questions

•What is the voltage output of the card terminal's cash drawer port?

Use a multimeter to measure the voltage when the open-drawer command is sent. Compare to the specified voltage (12V or 24V DC).

•Is the RJ11/RJ12 cable shielded? Is a shielded cable required by the card terminal manufacturer?

Unshielded cables are more susceptible to electromagnetic interference (EMI). Check the manufacturer's specifications for cabling requirements.

•Has the card terminal software been recently updated? If so, roll back to the previous version to test if the issue is software-related.

Sometimes software updates introduce unintended bugs that can affect peripheral device functionality.

Cash Drawer Failure: Post-Refund Diagnostic and Resolution

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•What is the voltage output of the card terminal's cash drawer port?

•Is the RJ11/RJ12 cable shielded? Is a shielded cable required by the card terminal manufacturer?

•Has the card terminal software been recently updated? If so, roll back to the previous version to test if the issue is software-related.

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: