Cadillac 2007 CTS, Owner'S Manual, Page: 116 / 518

Engine Coolant Heater
Your vehicle may have an engine coolant heater.
In very cold weather, 0°F (
−
18°C) or colder,
the engine coolant heater can help. You will get
easier starting and better fuel economy during
engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your
vehicle. At temperatures above 32°F (0°C), use of
the coolant heater is not required. Your vehicle
may also have an internal thermostat in the
plug end of the cord. This will prevent operation of
the engine coolant heater when the temperature
is at or above 0°F (
−
18°C) as noted on the cord.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical
cord. For the 2.8L V6 and the 3.6L V6
engines, the cord is located in the engine
compartment on the passenger’s side of the
vehicle in front of the fuse block. For the
6.0L V8 engine, the cord is located in
the engine compartment on the driver’s side
of the vehicle near the inner fender and above
the strut.
Remove the plastic cap to access the plug.
3. Plug it into a normal, grounded 110-volt AC
outlet.
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