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A comment on Why do they still make car alarms? (2015). Parent comment

Re:Why do they still make car alarms? (2015) by seany on Tuesday January 19, 2021 @06:13PM (#25840260)
If it's a DC pump the alarm probably just turns on a relay that swaps the input polarity of the motor.
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Re:Why do they still make car alarms? (2015) by spiritplumber on Tuesday January 19, 2021 @07:36PM (#25841078)
Yep. It comes with a relay and I wired it to another DPDT relay. It's supposed to go on the carn horn terminal instead.

I love how older vehicles have really simple wiring.

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