Last Updated10th of January, 2012
- Inspect sensor in bright light for cracks or flaws.
- Place 4.0 standard solution on sensor and attempt reading. Failed sensors generally cannot read to the pH 4 solution. If so replace sensor.
- Test and/or replace batteries. CR2032 3V Lithium batteries are available at most electronic retailers. Replace batteries when "B" shows on the display.
- Condition sensor. Cover sensor in either standard solution and soak for 15 minutes. Rinse and attempt calibration.