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Install GPay kit 4004-001-2 on MDC or Quantum dual-coin machines

Install the Greenwald Pay Plus device between the MDC/Quantum control board and coin drop.

  • Kit: 4004-001-2
  • Installation sheet: INS. 2472-3 Rev A

Installation layout

MDC/Quantum dual-coin Greenwald Pay installation connection layout

What you need

  • Greenwald Pay machine labels
  • Appropriate tool or operator key to open the machine panel
  • Smartphone with the Greenwald Pay app

MDC/Quantum dual-coin Greenwald Pay installation kit and required tools

Before you begin

  • Create the room and machine profiles in Greenwald Management System (GMS).

  • Confirm the exact machine model, controller, and kit number.

  • Disconnect machine power before opening the console or changing connections.

Install the hardware

  1. Open the console panel and disconnect the existing coin harness.

  2. Connect the Greenwald Pay device where the coin harness was connected on the control board.

Greenwald Pay control-board connection

  1. Connect the machine coin harness to the Greenwald Pay device.

  2. Connect the Greenwald Pay serial plug to the control-board serial port.

  3. At the machine power-supply transformer, disconnect the output connector. Insert the power tap, reconnect the power leads, and secure the tap with the included double-sided tape. Polarity does not matter.

Greenwald Pay power tap installed at the transformer output

  1. If the power connector is full, attach the power leads with the supplied IDC splices.

IDC splice connections for a full power connector

  1. Confirm that the serial/purse jumper is installed.

Configure the device

  1. Leave the console open and restore machine power.
  2. Wait for initialization. A slow-blinking white LED means the device is not configured and is ready to pair.
  3. In the Greenwald Pay app, sign in with administrator credentials and select Setup.
  4. Select the correct account and location.
  5. Select the device, then select the machine assignment that matches the physical machine label.
  6. Confirm that the MAC address shown in the app matches the MAC address on the device.
  7. Label the washer or dryer with its machine number.
  8. Repeat for every machine.
  9. Close all console panels when setup is complete.

For additional help, call Greenwald Customer Service at 800-221-0982.

Device LED codes

Color Activity Meaning
Off Off Device not connected to power
White Slow blink Device not configured
Blue Steady Selected during configuration
Yellow Slow blink Loading machine configuration
Green Steady Configured and ready
Blue Slow blink Active with phone app
Green Fast blink Active; Start not pressed
Green Slow blink Busy; machine running
Red Slow blink Machine error
Red Fast blink Machine interface error
Blue/Green Slow toggle Firmware loading
Red Steady Firmware error

Machine error codes

  • EC18 or EC19 - No communication between reader and control board: Check the serial/purse jumper where applicable, inspect all wiring, and confirm setup while noting the Greenwald Pay LED color.
  • EC11 - Initialization error: Power the machine down, power it up, and try again.
  • EC1A - Payment-system initialization on a Front End Control-only system: Change the GMS machine configuration.
  • EC05 - Invalid data from reader: Confirm the machine type. Verify that at least one programming option is valid and within range.

Original installation sheet

Download INS. 2472-3 Rev A. The same PDF remains attached to this page.