Map spinning on a GPSMAP

Cause of Spinning Map

If the Map page of a GPSMAP chartplotter appears to be spinning, this is usually due to the GPS accuracy. A spinning map primarily happens when the boat is sitting still or moving very slowly, and the map orientation is Course Up or Track Up. GPS accuracy is generally 3 meters or greater at times. The device does not know the boat's true heading. When the map orientation is set to Course Up or Track Up, the chart is trying to display the boat's heading to the top of the screen. To resolve this issue, see the steps below.

Change the Map Orientation

The first step is to change the Map Orientation to North Up; this will allow the map to display North always at the top of the screen of the chartplotter. To change this setting, please follow these instructions:

Legacy¹ GPSMAP units:

From the Navigation chart > Menu > Chart Set up > Chart Appearance > Orientation > North Up

Current¹ GPSMAP units: 

From the Navigation Chart select Options > Settings > Map Orientation > select North Up

Add a Heading sensor to the vessel

If North Up orientation is not preferred, another way to correct this issue is to install a heading sensor to the chartplotter to provide constant heading information to the chartplotter when the boat is not moving. For more information about heading sensors, see Heading Sensor Recommendation for use with Garmin Chartplotters.

Change the Speed Filter

Lastly, if a heading sensor cannot be used, a setting called Speed Filter can be changed to try and correct this issue. Speed Filter is a setting that allows the unit to average the speed readings to make it appears as a more gradual change instead of fluctuating at large intervals.

The setting may be in a different location depending on which chartplotter and GPS antenna is being used.

Bare wire connected antennas

Legacy GPSMAP¹ with a GPS 17N, GPS 17 HVS, GPS 17x HVS or GPSMAP 19x HVS (bare wire) antenna, please follow these instructions:

From the Home Screen press Configure > Communications > Serial GPS > Speed Filter > ON > enter a time of 2 seconds, then press the done button. 

Current GPSMAP¹ devices using a GPS 17N, GPS 17 HVS, GPS 17x HVS or GPSMAP 19x HVS (bare wire) antenna, please follow these instructions:

From any page press Options > Settings > System > GPS > Speed Filter > set to ON, enter a time of 2 seconds, and press the done button. 

NMEA 2000 Connected Antennas

Legacy GPSMAP¹ with a GPS 19x NMEA 2000 17x NMEA 2000 antenna, please follow these instructions:

From the Home screen select Configure > Communications > NMEA 2000 Setup > Device List > highlight the GPS antenna, press the Review button > Speed Filter > Set to ON > enter a time of 2 seconds, press Done.  

Current GPSMAP¹ devices using a GPS 19x NMEA 2000 17x NMEA 2000 antenna, please follow these instructions:

From the home screen select the Options > Settings > Communications > NMEA 2000 Set up > Device List > highlight the GPS antenna Press the Review Button > Speed Filter - set to  ON, enter a time of 2 seconds, press Done. 

The Speed Filter Setting has three choices:

• Off - This setting will turn the Speed Filter setting off so the unit will not average the speed reading.
• Auto - This setting will make the unit automatically control the speed filtering.
• On - This setting will allow the unit to manually control the speed filter by entering a value in seconds. As an example, if this value was set to 5 seconds, the GPS until will record your speed readings and average them over those 5 seconds to provide a gradual change in the speed reading.

^{1 Legacy GPSMAP devices 4000 / 5000/ 6000 / 7000 series devices}

^{1 Current GPSMAP devices  7400 / 7600 / 8400 / 8600 / 702 / 902 / 1202 / 703 / 903 / 1203}