GMC Cadillac CTS 2004 Owner's Manual page 201

Service Air Bag
There is a problem with the airbag system when this
message appears. Have your vehicle serviced by your
GM dealer immediately. See Airbag Readiness Light
on page 3-42 for more information.
Service Charging System
This message will display when a problem with the
charging system has been detected. Have your vehicle
serviced by your GM dealer.
This symbol appears
with the Service Air
Bag message.
This symbol appears with
the Service Charging
System message.
Service Electrical System
This message will display if an electrical problem has
occurred within the Powertrain Control Module (PCM) or
the ignition switch. Have your vehicle serviced by
your GM dealer.
Service Fuel System
The Powertrain Control Module (PCM) has detected a
problem within the fuel system when this message
appears. Have your vehicle serviced by your GM dealer.
This symbol appears with
the Service Electrical
System message.
This symbol appears
with the Service Fuel
System message.
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