User's Manual

Table Of Contents
Dexcom G5 Mobile System User Guide
Troubleshooting
320
Device
What you see
Problem What you do
BG Meter
Sensor
readings and
BG meter
glucose values
often don’t
show the
same.
See Chapter 7.
Differences are not
uncommon.
Readings from different
body fluids reflect
different numbers:
Meter
- from blood
Sensor
- from interstitial
fluid
20/20 Rule
If the meter shows 80
or less, CGM should
read within ± 20 points.
If the meter shows 80
or above, the CGM
should read ± 20%.
Example: a 202 mg/dL
sensor reading and a
188 mg/dL glucose
meter value = a 7%
difference (this is still
considered accurate).
Outside of 20/20 rule:
Calibrate again.
Smart
Device:
In App
Receiver
Device
What you see
Problem What you do