I get "No fix. Waiting..." message on the phone.

Properties ID: 000049
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"No fix. Waiting..." message means the phone cannot fix the position with the satellite. This could be because the satellite view was blocked by the buildings or other obstacles surrounding the phone (for example skyscrapers in downtown), or the GPS permission setting on the phone is denying GPS access.

Troubleshooting Steps: 

  1. Check GPS permissions on the phone.

    For Motorola iDEN i### series phones (Nextel, Boost Mobile phones):
    • Press the menu button, select "GPS"->"Privacy"->"Unrestricted". This will allow Java programs to access the GPS chipset.
    • Press the "menu" key and go to "Games & Apps" (you may need to select "More" before seeing "Games & Apps"), highlight "AccuTracking", then press "menu" key again,  select "Permissions" and make sure "Location" is set to "Always"

    For Blackberry phones:
    Check "Options" > "Location Based Services" > "GPS Services" > "Location ON". Then go to "Settings" > "Options" > "Security Options" > "Application Permissions".  Highlight the item for "AccuTracking", press the menu key, and select "Edit Permissions".  Highlight the "Connections" item, press the menu key, and select "Expand".  Make sure the Location (GPS) item is set to "Allow".

  2. Try to move to a different place with a good view of the sky and hold the phone for a few minutes. When it gets a position fix, the screen will show "Sending...", then "Sent TIMESTAMP". Your position can be viewed online now.
  3. If the phone still cannot get a fix, try to use the built-in GPS application that comes with the phone and see if it works. If it doesn't, this could be a GPS hardware issue. On Boost Mobile phones, the built-in GPS application can be found under "menu" > "More" > "More" > "GPS".

Note: If the phone GPS chipset has not been used for a long time (days or weeks), particularly in the case of new phones, the first GPS fix is usually tough to get and takes quite some time (minutes even hours). The reason is the phone needs to wait for the satellite almanac updating data from the satellite broadcast stream (satellite almanac data change from time to time and expires automatically after a few hours). Once the first fix is acquired, the phone GPS chipset caches the latest almanac data and use them in the following GPS fixes.  So the following fixes should be pretty quick.

Tip to get the first fix faster:

1) Have the phone stay in one place with a good view of the sky and don't move till it gets the first GPS fix. If the phone is moving while it tries the first GPS fix (for example, in a moving car), it'll be harder to get the first fix.

2) Force the phone to flush the old almanac data and obtain the new almanac by powering cycle the phone. When the phone GPS chipset has an outdated copy of almanac data and uses it as the basis for the following GPS fixes, it can take much longer for the phone to acquire a fix because the almanac data is wrong. "Wrong almanac is worse than no almanac". This can happen when the phone was used outdoors, then turned off, and next time is powered on with no sky view (indoors, underground). In this case, restarting the phone will clear the outdated almanac and obtain a refresh copy from the satellites.

For more technical background on almanac data and why the first GPS fix is slower, see here.

Question: I installed the phone in the car and it worked well for a few days, then stopped tracking. I then took the phone out and it worked again. I put it back into cars, it kept working. My car hasn't moved a bit so I think the sky view didn't change. How come?

Answer:  The key to understand this is "the first fix is the hardest to get and requires better view of sky than the following fixes" (see the note above). So when you install in the car, it already had the first fix. Even with a bit poorer sky view in the car, it can still get the following fixes. However, at some point the sky view went to a point that the phone lost fix for some time and requires new satellite almanac data for a fix. It could never get its first fix, because the first fix requires higher quality of sky view. Until you took out the phone again with a better sky view it was able to get the first fix again. When you put it into the car again, it'll keep fixing till it loses fix again.

Also, the sky view varies on the clouds, weather, trees, reflections from buildings etc., even the phone is staying in one spot.



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