Chevrolet Tahoe 2008 Owner's Manual page 35

A 20 amp fuse protects the flasher module circuit. This
fuse is located in the underhood fuse block in the engine
compartment on the driver's side of the vehicle and is
labelled HEADLAMP WASH. See "Fuses and Circuit
Breakers" in the Service and Appearance Care section
of your Tahoe owner's manual for more information.
Forward Lamp Harness In-Line Connector for use with Headlamps Flasher Module, Option 6J7
When it is dark outside, the taillamps will turn on
automatically. The Center High-Mounted Stoplamp
(CHMSL) will not flash and will operate only when the
regular brake pedal is pressed.
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