Uploaded March 2021 | Updated September 2026, 2 weeks ago

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Recorded: Mon, Mar 15, 2021
Published: Mon, Mar 15, 2021
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Fiber optic tally lights have been around for years on Cadillacs. To summarize briefly, they tell you whether a bulb is lit, without actually being light bulbs themselves.
If the fiber optic light works, the lamp works. If it doesn’t, then the lamp is burned out and needs replacing.