My GPSI-3900 Stopped Tracking

Confirm that the vehicle is parked out in the open and is with cellular coverage. From the Manage Vehicles page, ping the unit using the refresh icon  next to the vehicle’s last ‘Reported’ date/time, or contact Tech Support with the unit’s serial number for the initial unit assessment.

Ignition Detection Issue

This issue may occur if the unit responded to the ping with the correct GPS location.

  1. Verify the unit is seeing 12V on the white wire when the ignition is turned On.
  2. If not, confirm the inline fuse is not blown and troubleshoot the issue. White wire should only see 12V when the key is turned into ignition. You should see 0V when in accessory or in the Off position to avoid false idling events.

Antenna/Unit Placement Issue

This issue may occur if the unit responded to the ping with an incorrect GPS location.

For INTERNAL Antenna (GPSI-3900I) devices, check the following:

  1. Confirm nothing metallic is being placed on the dash which could be blocking the unit from acquiring satellites.
  2. Locate the unit and make sure it’s placed high within the dash and the white sticker side is facing up. Dashboard plastic and the windshield should be the only things impeding the unit from acquiring satellites.
  3. If the Green light is still flashing, with the ignition Off and parked in an open area, unplug the GPS unit for 10 seconds and plug it back in. After approximately 2 minutes the GPS light (Green) should go solid.
  4. If the light does not go solid, (from the vehicle) contact Support to get further assistance.

For EXTERNAL Antenna (GPSI-3900E) devices, check the following:

  1. Confirm the antenna is placed on the windshield. Bottom left or right corner is recommended.
  2. Confirm the antennas connections are screwed into the unit, finger tight.
  3. Follow the cable from the unit to the windshield making sure there’s no damage to the antenna cables; a small pinch could break the coax wire.
  4. If everything looks good, reset the unit. With the ignition Off, unplug the harness from the GPS for a minimum of 10 seconds and then reconnect.
  5. If the green light does not go solid after five minutes, replace the antenna:
    1. Disconnect the unit from power by unplugging the 20pin Molex connector.
    2. Unscrew the antenna connections.
    3. Screw on the new antenna making sure the antenna connections are finger tight.
    4. With the vehicle Off, reconnected the 20pin Molex connector. Do not start the vehicle until the lights go solid.
    5. If the lights do not go solid after replacing the antenna, contact Support from the vehicle.

Power or Cellular/Antenna Issue

If the unit did not respond to the ping, another issue may be the cause.

  1. For External Antenna: Verify the antenna is properly mounted on the windshield with the sticky side facing the sky and the exposed antenna cables are not damaged.
  2. Are you in an area with good cellular data coverage?
  3. Verify the inline fuse on the red wire is not blown and the unit is being provided with 12V or more.
  4. Verify the Ground wire has a good connection with the chassis.
  5. Test the power going to the unit by using a multimeter and placing the probe on-top of the inline fuse and against the connector you’re using for a ground. Is the unit getting +12V?
    1. No Power: Move ground wire to a new source and test.
    2. Unit Has Power: Confirm the harness is connected to the unit, and confirm whether or not the GPS units red light is On, OFF, or Flashing:


      1. Unit has cellular connection. Contact Support for further assistance.


      1. Internal Antenna – Make sure the unit is placed high in the dash white sticker side facing up.
      2. External Antenna – Make sure the smaller of the two antenna connections is connected to the unit (finger tight); follow the cable to the antenna making sure the cable is not crimped or cut. Antenna should be mounted on the windshield, lower left or right corner.
      3. With the ignition Off, unplug the unit for 10 seconds and then reconnect. Wait 1-2 minutes for the lights to go solid.
      4. If the lights do not go solid, contact Support.


      1. Confirm power to the unit and unit is properly connected by connecting the red and black wires to a battery.
      2. If the unit powers-up double check the wiring again.
      3. If the unit does not power-up contact Support with the unit connected to the battery and request a replacement.

More reference materials:

device not receiving power
no device power
device power