E-3
OneTouch Blood Glucose Meter
Severity: MinorWhat Does This Error Mean?
E-3 means the meter's environment is too cold (below 6°C / 43°F) or too hot (above 44°C / 111°F) for a reliable test. Test strip chemistry is temperature-sensitive — readings outside this range can be dangerously inaccurate. Move to a room-temperature environment and wait 5 minutes before retesting.
Affected Models
- OneTouch Verio
- OneTouch Verio Flex
- OneTouch Verio Reflect
- OneTouch Ultra 2
- OneTouch Select Plus
How to Fix It
-
Move to a comfortable indoor environment
Bring the meter and strips indoors to a room between 15°C and 30°C (59°F–86°F). E-3 is common in cold weather when the meter has been in a coat pocket, car, or bag outside.
-
Allow 5–10 minutes to stabilise
After moving to the correct temperature, wait at least 5 minutes before testing. The meter warms up faster than the test strips — both must be at room temperature before a reliable reading is possible.
-
Keep strips and meter at room temperature
Store test strips between 4°C and 30°C (39°F–86°F). Do not refrigerate strips unless the product label specifically instructs it. Avoid leaving the meter in a car during hot summers or cold winters.
Frequently Asked Questions
Is E-3 a sign of meter damage from extreme temperatures?
Usually not. E-3 is a protective alert that prevents inaccurate readings — it does not mean the meter is broken. However, exposing the meter to extreme temperatures repeatedly over time (for example, leaving it in a hot car regularly) can eventually degrade the internal components.