Refer to the tables below when Duro or Duro Inertial unit does not function properly.

Many issues are caused by an incorrect device configuration. Often, the easiest and quickest remedy is to update device to the latest firmware, reset firmware to the default settings and configure device step-by-step as required.


SymptomPossible CauseRemedyNotes
The unit fails to turn on (no green LED on the front panel).The power cable is not connected properly or power source is not on.Connect power cable firmly and check power source.
Power supply polarity is incorrect or voltage is too low or voltage is too high.Check power supply polarity, measure supply voltage.Supply voltage must be between 10 and 35 V DC, 1 A minimum.
Device is broken.Contact Swift Support.Current consumption is a good device health indicator. Duro should take about 0.4 A at 12.0 V during normal operation.
The unit fails to start (green LED is on but no any other LED is on and no data is output on any interface port).Loaded firmware does not start properly.Check if three white LEDs blink about 10 seconds after power up. If they do then the software starts properly, if not - the firmware didn’t start - contact Swift Support.
Device is configured incorrectly.Command Reset to Defaults when connected with Swift Console. If not possible to establish communication over both serial ports and Ethernet, carefully open the back door and use micro USB cable to connect Duro to PC; then open Swift Console over the new virtual serial port created and command Reset to Defaults.Never use back-door USB for normal operation. It’ll void the warranty. That port is intended for device recovery only.

GNSS Signal Reception

SymptomPossible CauseRemedyNotes
The unit fails to detect GNSS antenna (front panel yellow LED is off).

GNSS antenna or RF cable is not connected properly.

Check antenna and antenna cable connections.

GNSS antenna or antenna cable is broken.

Use different GNSS antenna and/or cable.

Antenna bias is turned off or not primary antenna is selected.

Change antenna_bias settings to True and antenna_selection to Primary in the frontend settings group.

Need to select Show Advanced Settings in Swift Console to see frontend settings group.

Antenna bias is not present despite of correct settings (measure DC voltage at TNC RF input, it should read about 4.85 V).

Contact Swift Support.

The unit fails to receive GNSS signals (yellow LED on the front panel blinks slowly).

GNSS antenna is in the place where no GNSS signals are present (indoor, in the tunnel, underground parking).

Move GNSS antenna to an open sky view area.

Incorrect antenna is used.

Use antenna provided by Swift Navigation or other recommended antenna.

Active antenna is required.

RTK Operation

SymptomPossible CauseRemedyNotes
The unit fails to operate in any RTK mode (front panel blue LED is off).

Note: Duro must have a valid autonomous fix (yellow/purple LED must be on) for any RTK to operate.

Base station is not operational or is not receiving GNSS signals.

Check base station operation.

Radio link with a base station is broken.

Check the radios, radio cables and radio antennas on base and rover.

To verify if the radio link  is an issue disconnect radios and connect base and rover with RS232 cable and null modem adapter (if distance is feasible).

Duro is not connected to the Internet for NTRIP client operation (red LED is not on).

Check Ethernet cable connection and network switch/router if it has Internet access.

Duro is receiving correction data from multiple sources simultaneously.

Configure Duro to use corrections from one source only or disconnect cable from undesired data source.

The unit fails to operate in RTK fixed mode (front panel blue LED is blinking but never goes solid on).

Device is configured to use Skylark correction service.

RTK float is a proper positioning mode when Skylark is used. No any action is required, this is correct operation.

Base station is too far away.

Use closer base station or move closer to the base.

RTK should be used within 50 km from the base station for the best results.

Incorrect lat/lon/alt position in RTK mode.

Base station provides its coordinates in a different reference frame.

Change base station settings or use a different base station.

Duro provides altitude from ellipsoid only. Altitude from MSL (geoid) is not available.

It takes a long time to converge to RTK fixed solution.

Base station is too far away.

Use closer base station or move closer to the base.

Base and rover do not have many common satellites and signals.

Check base and rover settings if they have the same constellations enabled and use the same bands (L1 and L2).

GNSS signals are affected by an interference.

Check signal levels. Remove interference source or move GNSS antenna away.

Operation with Swift Console

SymptomPossible CauseRemedyNotes

No any data is shown on Swift Console windows.

Cable connection to Duro is broken.

Check cables and interfaces used. Is the right port being used?

Usually (and by default) Duro UART1 (on AUX port) and TCP Server 0 (on Ethernet port) are being used for communication with Swift Console.

Port settings on Duro do not match with PC settings.

Check baud rate on serial port, check IP address and port on Ethernet interface.

No data on any tab except Observations tab.

PC with Swift Console is connected to the Duro serial port UART0.

Connect PC to the Duro port UART1 on the AUX connector.

By default UART0 port outputs only observation data (like a base station).

No data on Settings tab but data on other tabs is present when connected with RS232-USB cable adapter.

Broken RS232-USB cable.

Use different cable adapter.

If different cable works contact Swift to obtain a free replacement cable.

New settings are not preserved over the power cycle or software reset.

Settings were not saved to the non-volatile memory before power cycle or reset.

Click Save to Device button on Swift Console to make the change permanent.

Error window ”Settings Write Error” shows up when trying to change interface port settings.

Change is made to the same port that is being used for Swift Console communication.

Use different communication interface port (eg. use Ethernet to change UART1). Never use UART1 to change UART1 settings.