This article is from the Toyota Tundra FAQ, by Steve Yee with numerous contributions by others.
Many people have asked as to why the cargo light shuts off when the Tundra
begins to move. The cargo light is wired in such a way that when your Tundra
goes faster than 3 miles per hour, the cargo light shuts off. An Arizona
Neurosurgeon who is a Tundra owner has published a detailed web page showing
what mods to peform if you would like better control of your cargo lamp. His
page for the cargo lamp mod can be found at:
http://www.fastq.com/~louvu/cargolightmod.htm .
 
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