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Calibrate the Accelerometer

The PN-40 contains an accelerometer. During compass calibration, the unit uses the accelerometer to determine which way is down. If you are unable to calibrate the compass, you may need to recalibrate the accelerometer first.

Everybody encounters an occasional failure to calibrate the compass. After all, the "dance" is complicated. An occasional failure is not a reason to recalibrate the accelerometer. On the other hand, repeated failures, especially if they occur immediately upon attempting to calibrate the compass, may be a reason to do so.

See Compass & Altimeter Settings for details.

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Recalibration of the accelerometer requires you to put the unit in Support Mode. WARNING: Using support mode without DeLorme Technical Support assistance may cause serious problems. Use Support Mode at your own risk.

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To recalibrate the accelerometer:

1. Turn the PN-40 off.
2. Press and hold down the Page and Menu buttons.
3. Press and hold down the Power button (the small red button).
4. Once you see the dark blue warning screen (it takes 3 to 4 seconds), release the Power button first, then the Page and Menu buttons.
5. Press the Enter button to acknowledge the warning and proceed to Support Mode.
6. Use the 4-way arrow button to scroll down to Test, and press the Enter button.
7. Scroll to Debug Compass and press the Enter button.
8. Lay the device perfectly flat. This is important.
9. Press the Menu button once to calibrate the accelerometer. Nothing visible will happen.
10. Press the Quit button as many times as necessary to return to the first page.
11. Scroll to Reboot and press the Enter button.

After the reboot, calibrate the compass.

1. Go to the Satellite page and press the Menu button.
2. Scroll to Calibrate and press the Enter button.
3. Scroll to Calibrate Compass and press the Enter button.
4. Follow the on-screen directions to the dance.