> For the complete documentation index, see [llms.txt](https://docs.verifone.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.verifone.com/hardware-products/hardware/android-devices/t650-series/t650c/t650c-installation-guide/troubleshooting-guidelines.md).

# Troubleshooting Guidelines

The troubleshooting guidelines provided in the following section are included to help you install and configure your T650c successfully. Typical examples of malfunction you may encounter while operating your T650c device and steps you can take to resolve them are listed in this chapter.

If the problem persists even after performing the outlined guidelines or if the problem is not described below, contact your local Verifone representative for assistance.

{% hint style="info" %}
The T650c comes equipped with tamper-evident labels. The T650c unit contains no user serviceable parts. Do not, under any circumstance, attempt to disassemble the device. Perform only those adjustments or repairs specified in this guide. For all other services, contact your local Verifone service provider. Service conducted by parties other than authorized Verifone representatives may void any warranty.
{% endhint %}

{% hint style="warning" %}
Before troubleshooting, ensure that the power supply being used to power the device matches the requirements specified at the bottom of the device. (See Specifications, for detailed power supply specifications.) Obtain the appropriately rated power supply before continuing with troubleshooting.
{% endhint %}

## Device Does Not Start

If the device does not start:

* Ensure that the device is plugged into a dedicated power source.
* Check if the power cable connector is plugged in properly.

## Device Display Does Not Show Correct/Readable Info

If the device display does not show correct/readable info:

* Check all the cable connections. If the problem persists, then contact your local Verifone representative for assistance.

## Blank Display

When the device display is blank:

* If the device display is dark, tap the screen with the stylus or your finger. If the unit was in screen-saver mode, the screen will turn on when touched.
* If the display does not show correct or readable information, then check all the cable connections. If the problem persists, then contact your local Verifone representative for assistance.

## Keypad Does Not Respond

If the keypad does not respond properly:

* Check the device display. If it displays the wrong character or nothing at all when you press a key, follow the steps outlined in Transactions Fail To Process.
* Refer to the user documentation for that application if pressing a function key does not perform the expected action to ensure you are entering correct data correctly.
* Contact your local Verifone representative if the problem persists.

## Transactions Fail To Process

There are several possible reasons why the unit may not be processing transactions. Use the following steps to troubleshoot failures.

### Checking Magnetic Card Reader

To check magnetic card reader:

1. Perform a test transaction using one or more different magnetic stripe cards to ensure that the problem is not a defective card.
2. Ensure that you are swiping cards properly (see Using the Magnetic Card Reader).
3. Process a transaction manually using the keypad instead of the card reader. If the manual transaction works, then the problem may be a defective card reader.
4. Contact your local Verifone representative if the problem persists.

### Checking Smart Card Reader

To check smart card reader:

1. Perform a test transaction using several different smart cards to ensure the problem is not a defective card.
2. Ensure that the card is inserted correctly (see Using the Smart Card Reader).
3. Ensure that the SAM cards are properly inserted in the slots and are properly secured.
4. Contact your local Verifone representative if the problem persists.


---

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