MEI Bill Acceptor - Troubleshooting Common Issues - Operator Guide


This purpose of this article is to explain how to maintain and troubleshoot various issues that you may encounter with the MEI Bill Validator as an operator. 

MEI Bill Validator:
Gen2, Gen 3, Gen3c, and V5 MicroMarkets



  • Phillips-Head Screwdriver
  • Key to XP (Expansion) Unit or Back of Kiosk



Care & Usage

For information on error/flash codes and maintaining the bill acceptor, view our article, MEI Bill Acceptor - Care & Usage


Testing the Bill Acceptor

Important: To perform the following steps you must have a valid kiosk account and kiosk PIN created on SmartHQ and enabled with the Settings permission. To request a kiosk user account, contact your management team. Read more at Managing Kiosk Users - Technicians & Drivers. If you are not authorized to have a kiosk user account with your organization, contact us while on-site to complete the following steps with a 365 Technical Support Specialist. 

The bill acceptor has lights on the front that will only illuminate when the device is waiting for a bill to be inserted. You can test the acceptor in the Point of Sale software by prompting the device to turn on.

  1. From the kiosk Home screen, tap the top, left corner five times. A window will appear and prompt you to enter your Exit Code. Enter the Kiosk PIN for the Kiosk User account on SmartHQ.

  2. Select Kiosk Settings from the drop-down menu.

  3. Select Bill Acceptor from the Select A Peripheral drop-down menu.

  4. Click the Test Acceptor button.


Successful: "Insert Bill, Insert Bill, Insert Bill..."

If working properly, the Acceptor Status will display "Validator Ready" followed by "Insert Bill". The front of the bill acceptor will light up to accept a bill. Test it with several bills of various denominations. If all are accepted, the validator is working properly. 



Unsuccessful Test: "Validator Ready"

If that field says "Validator Ready" but does not add additional lines showing "Insert Bill" above it every one second, the computer is not sensing that the bill acceptor is connected. The COM Port assignment may be incorrect. Tap the COM Port drop-down menu and test COM ports one through five to determine if it is connected to a different COM port. If the validator moves to "Insert Bill" on a different port, select Save to apply the correct COM port assignment and return to the Point of Sale checkout screen.



Unsuccessful Test: "Access to COM 1 is denied"

If the access to the port is denied, verify the COM Port that the Bill Acceptor is connected to. Power cycle the bill acceptor by powering down the PC and then turning off the supply for the kiosk XP (Expansion) Unit. Boot it back up and test the bill acceptor again. Verify that it moved to "Insert Bill" successfully. If changing the assignment to a different COM port, tap Save to apply your changes.



Unsuccessful Test: "Index was outside the bounds of the array"

After the error occurred, COM1 port would hang. Power cycle the bill acceptor by powering down the PC, then turning off the power bar. Boot it back up and the bill acceptor test should be successful.
Tap Save to save the new settings when changing to another COM port.


Unsuccessful Test: No Response from Validator

If the bill acceptor does not turn on using any available COM port, check to see whether it is getting power and is properly connected to the kiosk computer.  


How to Replace the Bill Acceptor



Use the following scenarios to troubleshoot common issues with the MEI Bill Acceptor. For more information on troubleshooting using the bill acceptor status lights, see the Bill Acceptor: Care & Usage article. 


Bypassing Coupler/Cable for Common Troubleshooting

A common troubleshooting practice will involve bypassing the cable connection to the coupler to rule out cable issues. Do so by removing the Ribbon Cable or COM/USB adapter from the PC and connecting the Bill Acceptor directly to the PC. In some cases, it may be necessary to remove the Bill Acceptor from the XP module so that a direct cable connection (from PC to Bill Acceptor) will reach.

Use the following reference photos when attempting to bypass. 

Bill Acceptor Will Not Light Up or Power On

The bill acceptor has a light on the front of the device, but will only light up when the device is waiting for a bill to be inserted. Open the kiosk or (Gen3c XP Expansion Unit) to check the bill acceptor and verify that everything is plugged in correctly.

At the bottom of the back side of the bill acceptor is a small light panel, which will blink red if the unit is receiving power. If it is not blinking, check both ends of the power and data cables, and be sure they are plugged in securely.


Check the Connections

  • The top ribbon cable connects directly to the computer COM Port on a Gen2 kiosk. In a Gen3c MicroMarket, this cable connects to a COM port going from the XP Unit to the coupler on the lower, left side of the kiosk. In this model, another ribbon cable connects from the other side of this coupler, joining it to the kiosk computer. 
  • The bottom ribbon cable is the power cable, connecting to the surge protector.
  • The bottom ribbon cable is the bill acceptor power cable, and plugs into the 6-port power strip inside the kiosk or XP Unit.

Gen3c and V5 MicroMarkets: Check the Printer

In a Gen3 kiosk, the bill acceptor is located in the XP Expansion Unit, or the module tower located to the left of the kiosk. Both the bill acceptor and receipt printer will be connected to a power supply separate from the kiosk. Check if there are lights on the Epson receipt printer. If there are no lights on either device, that may indicate the XP Unit  itself is not plugged in.

There is a power strip at the bottom of the side-tower which should have an illuminated Power button. If that power strip button is not lit up, trace the cord to the UPS PowerVar/Battery Backup or outlet and be sure that the power strip is connected.


Two Lights Error: Disabled from the System

If the back of the bill acceptor indicator light is blinking twice for "Disabled from the System", this indicated that the bill acceptor is in a neutral state and there is no cause for alarm. The bill acceptor will remain in a neutral state until it is prompted to accept payment by the Point of Sale software. When a consumer adds cash to their account, the front of the device will display a green light and allow the consumer to add funds. It will return to a neutral state when the consumer has completed their transaction.


The Bill Acceptor Will Not Accept Any Bills

Verify the Status Light is blinking twice for Disabled from system and try reseating the cassette case. Check to be sure there are no bills stuck in the machine. If a light code other than 2 - Disabled from the System is being displayed, see the article Bill Acceptor: Care and Maintenance for further assistance. 

  1. Reseat the cash magazine and clean the path the bills travel using a can of condensed air. 

  2. Remove the bottom scanning plate by lifting up the chrome bar. Gently remove the scanning plate and inspect for any damage.

  3. After cleaning the device, power cycle the bill acceptor.

  4. Retest the device. If no bills are accepted again, complete the following steps to check the COM port assignment.

Confirm the COM Port Assignment

If you have completed the steps above and the validator still will not accept any bills, the COM port settings may not be correctly configured in the Point of Sale software.

  1. Open the kiosk XP (Expansion) Unit. Remove the cash magazine completely, then re-seat it. (Refer to the sticker on the back of the magazine for removal instructions.) After the magazine has been reseated, test the bill acceptor again by completing the above testing steps.

  2. If if you have not already done so, clean the bill acceptor path using the instructions in the "Bill Acceptor is Jammed" section of the Bill Acceptor: Care and Maintenance article and test the bill acceptor again.

  3. If steps one and two do not resolve the issue, check which COM port the bill acceptor is physically plugged into. Tap Save to save your settings when changing to another COM port The COM ports on all computers inside 365 kiosks are labeled. 


Check the DIP Switches

Verify that the DIP switches on the side of the bill acceptor match those in the DIP Switch Image above.

  • Switches one through three should be turned to the LEFT.
  • Switches four through eight should be turned to the RIGHT.
  • If changes were made, reboot the entire kiosk and test the bill acceptor in Valet again. If no changes were made, power cycle the bill acceptor by powering down the kiosk PC, then turning off the power brick to the XP (Expansion) unit. After booting back up, test the bill acceptor again.


Some Denominations are Accepted, but not Others  

If some bill denominations are accepted, but others are rejected, check first to be sure that this is not a one-off situation with one or a couple bills of poor quality. Then clean the bill path using the instructions in Bill Acceptor: Care and Usage . Remove the cash magazine completely, then re-seat it. 

When the bill path has been cleaned, take a crisp, clean copy of the denomination that is failing from the magazine and test those in the bill acceptor. If good quality bills are still not accepted after testing, check to be sure that the settings are correct in the Point of Sale software.



Configurations in the POS Kiosk Settings

  1. Tap the top, left corner of the Point of Sale Checkout screen.

  2. Enter your Exit Code (PIN) when prompted.

  3. Choose Kiosk Settings from the drop-down menu.

  4. Make sure that Channels one through five are selected and their values are $1, $2, $5, $10, and $20 respectively.

    Additionally, the bill acceptor has eight DIP switches located on the side of the device that configure the acceptance options. Check to be sure the DIP switches are at the recommended settings. Check to be sure they are configured correctly by following the steps in the Check the DIP Switches section below.


Check the DIP Switches

Verify that the DIP switches on the side of the bill acceptor match those in the DIP Switch image above.

  • Switches one through three should be pointing to the ON direction.
  • Switches four through eight should be in the OFF position.


Monitoring Cash Acceptance

The Bill Acceptor performance can be remotely monitored by using the reporting tools in the 365 Market Administration web portals, which are SmartHQ and ADM. 



  • Cash In Summary - Summary of amount inserted into the validator and a physical bill count.
  • Cash In Detail - Records when a bill is inserted into the validator by denomination. 
  • Cash In Kiosk Report - Records Cash-In events performed when employees remove cash from the bill acceptor magazine.



  • Cash Audit Report - Cash Audit shows cash in and cash out, which is useful for finding cash out events.