Cadillac 2004 XLR - Manual (Page 247)

Coolant Surge Tank Pressure Cap
Notice: If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
See Engine Compartment Overview on page 5-12 for
information on location.
Engine Overheating
You will find an COOLANT OVER TEMP message or
an ENGINE HOT, STOP ENGINE message displayed in
the Driver Information Center (DIC). You will also
hear a chime. There is also an engine coolant
temperature gage on the instrument panel cluster. See
Engine Coolant Temperature Gage on page 3-49.
Overheated Engine Protection
Operating Mode
This operating mode allows your vehicle to be driven to
a safe place in an emergency situation. If an overheated
engine condition exists and the DIC message ENGINE
HOT, STOP ENGINE is displayed, an overheat
protection mode which alternates firing groups of
cylinders helps prevent engine damage. In this mode,
you will notice a significant loss in power and engine
performance. Driving extended miles (km) in the
overheat protection mode should be avoided.
Notice: After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss, change the oil and
reset the oil life system. See “Engine Oil” in the
Index.
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