> ## Documentation Index
> Fetch the complete documentation index at: https://nayax-44d6e37b-docs-marshall-faq-redistribution.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Marshall Troubleshooting

> Diagnose Marshall device startup, connection, and SIM failures

Each section below covers one Marshall failure: what brings it on, and what to
check to clear it.

## The Device Hangs on the Nayax Screen During Power-Up

A device that stops on the Nayax logo during power-up has a communication
problem. Any of the following can cause it:

* **Modem connection.** Poor cellular reception, or a poor Ethernet connection
  if the device is wired.
* **Wrong modem type.** For example, a European modem used in the United
  States, or a modem too weak for the location.
* **SIM card.** The SIM is missing, unsupported (such as a SIM bought outside
  of Nayax), or has used up its data.
* **Antenna.** The antenna is loose, wrapped around itself, pointing downward,
  or sitting against a metal enclosure.
* **Power supply.** If the device reaches the Nayax logo and then crashes,
  confirm the power source delivers 24V at a minimum of 1.5A. See
  [Marshall Hardware Specifications](/docs/integrate-pos-device/marshall/hw-integration-kit-and-setup/hardware-specifications).

## The Device Is in Cash Only Mode

If the device is connected to the Marshall cable but still runs in Cash Only
mode, the serial connection is not reaching the board.

Check which COM port is connected to your board. It must be COM2, as described
in [Installation Steps](/docs/integrate-pos-device/marshall/hw-integration-kit-and-setup/installation-steps).

If you use a Chipi-X USB-to-serial adapter, check whether it is connected
through a hub. Connect it directly to the PC instead.

<Note>
  The Chipi-X is the only USB-to-serial adapter that grants support privileges.
  Other adapters may work, but Nayax support does not cover them.
</Note>

## Everything Is Connected but Nothing Works

When the wiring and the device both look correct and the integration still does
not run, work through these checks in order.

<Steps>
  <Step title="Check the Nayax Core Parameters">
    Confirm the machine parameters in Nayax Core match your setup. See
    [Set Up Nayax Core for Marshall Integration](/docs/integrate-pos-device/marshall/hw-integration-kit-and-setup/set-up-nayax-core-for-marshall-integration).
  </Step>

  <Step title="Check the Physical Connection">
    Confirm the wiring matches
    [Installation Steps](/docs/integrate-pos-device/marshall/hw-integration-kit-and-setup/installation-steps).
  </Step>

  <Step title="Reboot the Device">
    Disconnect the device from power, wait for the screen to go black, then
    power it back on.
  </Step>

  <Step title="Check the COM Port in Your Code">
    Confirm the SDK code points at the correct COM port.
  </Step>

  <Step title="Compile and Run the SDK">
    Two things confirm the link is up: the peripheral simulator's menu and
    pairing process appear in the prompt window, and the log file shows the
    pairing process finished successfully.
  </Step>
</Steps>

## The SIM Card Is Not Working

Whether a SIM is recognized depends on the APN addresses stored on the device.
A SIM whose APN is not on the device does not work.

If a SIM has a problem, whether it shipped with the device or was bought from
Nayax separately, contact the support team at
[support@nayax.com](mailto:support@nayax.com).

## Next steps

<CardGroup cols={2}>
  <Card title="Stability & Starvation Issues" icon="triangle-exclamation" href="/docs/integrate-pos-device/marshall/additional-resources/stablity-issues">
    Diagnose the hardware causes behind an unstable or starved Marshall link.
  </Card>

  <Card title="SDK's Log Generation" icon="file-lines" href="/docs/integrate-pos-device/marshall/additional-resources/log-generation">
    Turn on SDK logging and find the log file to inspect peripheral traffic.
  </Card>
</CardGroup>