Power-On Self-Test

The self-test runs automatically after flashing or power-on, verifying the Hall sensor and magnet configuration.

What It Tests

The self-test verifies:

• Magnet detection: All 3 magnets are detected during one wheel rotation
• Even spacing: Magnets are approximately 120° apart (within tolerance)
• Signal quality: Clean transitions without noise or bounce
• Sensor connectivity: RJ22 cable is properly connected

Running the Self-Test

1. Power on the device or flash new firmware
2. The display shows “Self-Test” with instructions
3. Slowly rotate the wheel one complete turn (360°)
4. Maintain a steady pace — not too fast, not too slow
5. Wait for the result to display

Self-Test Failures

“Only X magnets detected”

The test detected fewer than 3 magnets. Possible causes:

• A magnet has come loose or fallen off
• Sensor is too far from the magnet path (should be within 5mm)
• You did not complete a full rotation
• Wheel was rotated too fast

“Uneven magnet spacing”

The magnets are not evenly distributed. This affects measurement accuracy.

• Verify magnets are positioned 120° apart
• Check that no magnets have shifted
• Re-mount magnets if spacing is incorrect

“No signal detected”

The Hall sensor is not sending any data.

• Check the RJ22 cable connection at both ends
• Verify the cable is not damaged
• Ensure the sensor is receiving power (3.3V)
• Test with a multimeter if available

Bypassing the Self-Test

To bypass the self-test, hold both buttons during power-on until the main menu appears. This is intended only for diagnostics.

Re-Running the Self-Test

To run the self-test again without reflashing:

1. From the main menu, navigate to Settings
2. Select “Run Self-Test”
3. Follow the on-screen instructions

Next Steps

After passing the self-test, proceed to calibration for maximum accuracy, or start using the device with the default calibration.