Troubleshooting - Devices Not Connecting

  Troubleshooting Guide

Please also see the attached flowchart at the end of this article

Troubleshooting your device

The main reasons a DM device is not performing correctly often comes down to one of four reasons.

  1. Power issues
  2. SIM card configuration
  3. GPS/Cellular Reception or network coverage
  4. Platform configurations

Power issues

Hard Wired Devices

If you have a device that's wired into a power source, this needs to be supplying at least 8V of power for the device to be consistently operating. For the Dart2, G120, G62 that have an internal backup battery, this can only power the device for a small amount of time, and generally if the backup battery voltage is less than 4V, it will be unreliable in it's operation.

The red wire on all wired harnesses needs to be connected to a point which supplies permanent power. If you find the device is only running while the vehicle/asset is operating, it could be attached to an incorrect power source.

Note that any voltage readings for a device that isn't currently connecting are only the value at the last update. 

Battery Powered Devices

Most of our latest cellular device range requires either Lithium Iron Disulphide (LiFeS2) or Lithium Thionyl chloride (LTC) batteries to operate correctly. Alkaline batteries will not perform well and shouldn't be used. Fresh LiFeS2 batteries will read about 5.2V and fresh LTCs will measure around 12V for three cells.

For devices that use a battery meter; Oyster2, Falcon & Eagle, check the battery percentage (analogue 6). 

 Battery Life and Estimates

For a more detailed discussion, see the discussion article here

If you have the device with you, The LED on the PCB should illuminate. If it switches on briefly and goes off, it may indicate that the power is not sufficient for the device to boot. It will wait until either external power is above 7V or the internal battery is above 3.5V. If either condition is true, the LED will start to flash slowly.

Check that the batteries are fresh, or have enough voltage under load to power the modem. When batteries are on the brink of low charge, they can sometimes have enough power for the LED flash, but not the modem. Typically devices on our latest firmware however will not show any 'signs of life' (won't flash the LED) if the battery voltage isn't sufficient to fully power the modem. 

SIM Card:


the SIM card should be of the correct size, or use a suitable adaptor plate, and be inserted with the correct orientation, with the golden pads facing the PCB. Check that the sim holder is latched closed securely.
The SIM usually doesn't have a PIN set. but if it does, the PIN can be retrieved from the OEM Server web interface.
Make sure the SIM card has credit / airtime or has had a communications plan and data plan enabled by contacting your provider.


A new device will be set to Auto-APN unless your distributor has made special arrangements. An in-service device may have been configured with a specific APN in the past. You can check the current settings in  OEMServer Admin Parameters.

If there is a currently pending Admin parameter update in the OEM Pending Updates column, that would be evidence that perhaps somebody has applied an incorrect setting. 

You can also see if anyone has previously played with the APN by checking out the User Activity Log in OEM. For any device, click the Details link in the device grid, and view the user activity tab. You will see SetDeviceAdminParameters

The LED will flash slowly until it connects to the server. Once connected it will flash fast. If data is sent, it will got solid briefly and revert to flashing fast.


Resetting an APN isn't a usual step for devices that have been deployed, rather for new devices that are struggling to get online with a new SIM card or network config.

No GPS/Cellular Reception

 GPS Troubleshooting

See our detailed guide on GPS debugging here

 Cellular Troubleshooting

See our detailed guide on Cellular reception debugging here

Platform Configurations

Devices not appearing in Telematics Guru

A device first appears in Telematics guru when it gets it's first valid GPS fix. You can see in Assets > Manage Assets whether a device has received a GPS position, this is shown with a red GPS icon. For a quick way to start generating GPS fixes, you can put the device into 'trip state' by taking it for a drive for example, or for a wired device connecting the white ignition wire to a power source while connected to external power.

Device committing to OEM Server but not Telematics Guru (or 3rd party server)

If your device is showing in Telematics Guru as 'Never connected' (see below) but is connecting into OEM Server, the connector might not be set.

 Setting a Connector

To learn how to set a connector, see our how to guide here

Forcing a Connection


There is no way to initiate a connection remotely because when the device sleeps, it switches off its modem. You will need to wait for the next scheduled connection – either a heartbeat, trip start or input change.

If you have the unit in your hands, you can force a connection by either removing the batteries or toggling the external power (for wired devices). This change will trigger an upload. Ensure the external power change is long enough to trigger the external power debounce period – 2 seconds by default.

You can also change any of the inputs set to trigger an upload. Usually ignition will trigger an upload. This depends on the system parameter configuration.

Debugging with OEM

The OEM Admin Interface is a powerful tool for understanding what your device is doing. See the OEM guide for detailed instructions. The following notes may help:

  1. Check when it last connected and if it committed records successfully.(All data displayed is from last committed time)
  2. Check to see if the connector is set to your correct endpoint
  3. Check external power and internal battery level.
  4. Enable the data log capture. Normally the OEM server forwards logs to the 3rd party software platform. You can View the logs in the Device Details->Logs tab.
  5. Enable debugging for a module. View the logs in the Device Details->Logs tab

OEM Server Installer page

A handy tool is the OEMServer Installer page that shows which the status of Power inputs, digital inputs, connection times and GPS Fixes.

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