turn signal hyper flash?

2008 CADILLAC CTS
180,000 MILES • 3.6L • V6 • 2WD • AUTOMATIC
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TERRY RIVEST
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rf turn signal hyper flash-replaced bulb-turn signal lever-still problem-rear works fine
Jan 9, 2026 at 10:44 AM
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STRAILER
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Does this car have LED's or has the bulbs been replaced with LED's? If the bulbs have been replaced with aftermarket LED's this is your problem. You must have the correct bulbs to supply the correct resistance or the blinkers will cycle to quick. I would replace the bulbs at the both the front and rear even if they work. I have seen bulbs work even though the resistance is off. Please let me know.
Jan 10, 2026 at 9:44 AM
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TERRY RIVEST
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has std bulbs
Jan 11, 2026 at 11:02 AM
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STRAILER
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If the bulbs are working replace them anyway. The BCM controls the bulb operation and if the resistance is wrong they will blink to fast. This can can tell you more.

https://www.2carpros.com/articles/turn-signals-blink-rapidly

Please go over this guide and get back to us.


Jan 11, 2026 at 11:04 AM
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CARADIODOC
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Hi guys. One more thing to consider that I've run into a few times is a non-working bulb that isn't recognized. This almost always happens in the rear. There can be two or even three bulbs in one rear corner, and they may have two filaments in each one, one for the tail light that still works, and one for the brake / signal that is dead. To check for that, use the hazard flasher so both sides flash at the same time, then they're easy to compare if both sides look the same.
Jan 11, 2026 at 7:47 PM