Where does the term "idiot lights" come from?

Dear Car Talk | May 01, 1993
Dear Tom and Ray:
Mary
RAY: You're right, Mary.
TOM: Many years ago, when my brother still had hair, cars had gauges. But that required interpretation. People had to know just how much oil pressure was good enough, and what temperature was too high.
RAY: This proved to be quite a challenge for some people...my brother for one. So manufacturers switched over to "idiot lights." "Idiot lights" require no interpretation. When the light comes on, you don't have to ask any questions, you just pull over and call for help. But believe it or not, we have customers who even ignore the "idiot lights."
TOM: So we're working on a more advanced warning system. It's a mechanical arm that comes up from behind the seat and gives the driver a crisp dope-slap. Now if I could only convince my brother to volunteer for the testing program.
Mary
RAY: You're right, Mary.
TOM: Many years ago, when my brother still had hair, cars had gauges. But that required interpretation. People had to know just how much oil pressure was good enough, and what temperature was too high.
RAY: This proved to be quite a challenge for some people...my brother for one. So manufacturers switched over to "idiot lights." "Idiot lights" require no interpretation. When the light comes on, you don't have to ask any questions, you just pull over and call for help. But believe it or not, we have customers who even ignore the "idiot lights."
TOM: So we're working on a more advanced warning system. It's a mechanical arm that comes up from behind the seat and gives the driver a crisp dope-slap. Now if I could only convince my brother to volunteer for the testing program.
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