EN–4 GTM 21 Instructions
Testing the Trafc Receiver
Observe the LEDs on the GTM 21: When the
GTM 21 is connected to power, the Power LED
is on. The GTM 21 may take up to ve minutes
to acquire data.
The Status LED indicates the status of the
GTM 21:
Yellow dot-dash ashes: determining which
country you are currently in.
Yellow solid light: searching for signal.
Red solid light: momentary signal loss.
Green solid light: normal trafc data.
Check the Map: Check the map on the GPS
device for trafc incidents or a trafc icon.
Refer to the owner’s manual.
Verify Signal Strength: If you are inside a
garage where radio signals cannot be received,
drive the vehicle outside.
Verify that you are in a service area: Check
for service from the pay service or free or
premium services.
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