GMC Cadillac CTS 2004 Owner's Manual page 194

Check Brake Fluid
This message will display if the ignition is in ON to
inform the driver that the brake fluid level is low.
Have the brake system serviced by your GM dealer as
soon as possible. See Brake System Warning Light
on page 3-43 for more information.
Check Coolant Level
3-74
This symbol appears
with the Check Brake
Fluid message.
This symbol appears
with the Check Coolant
Level message.
This message will appear when there is a low level of
engine coolant. Have the cooling system serviced
by your GM dealer as soon as possible. See Engine
Coolant on page 5-29 for more information.
Check Gas Cap
When this message appears on the display, the gas cap
has not been fully tightened. You should recheck the
gas cap to ensure that it is on and tightened properly.
See "If the Light Is On Steady" under Malfunction
Indicator Lamp on page 3-47 for more information.
This symbol appears
with the Check Gas
Cap message.