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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 turtlegrids on Tuesday January 19, 2021 @06:07PM (#25840201)
> The alarm is aftermarket, and silent. All it does is make the fuel pump go in reverse.

Would you mind disclosing what brand/model this alarm is? This would be great for a couple of “issues” I’ve been having.

If you aren’t comfortable saying publicly, could you send me a message with the info? And Amazon/Aliexpress/eBay link?

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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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Re:Why do they still make car alarms? (2015) by bagels on Tuesday January 19, 2021 @08:54PM (#25841652)
Seems like a really complicated kill switch.
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Re:Why do they still make car alarms? (2015) by fingerlocks on Tuesday January 19, 2021 @09:18PM (#25841811)
Exactly. Every fuel pump has a ground that you can put a switch on to kill it. No need to run it in reverse.
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Re:Why do they still make car alarms? (2015) by coryrc on Tuesday January 19, 2021 @09:33PM (#25841927)
Except old engines with mechanical fuel pumps like the GGP has
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Re:Why do they still make car alarms? (2015) by fingerlocks on Tuesday January 19, 2021 @10:57PM (#25842428)
GGP said it was an aftermarket electric fuel pump
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Re:Why do they still make car alarms? (2015) by spiritplumber on Thursday January 21, 2021 @10:20AM (#25859732)
Both; the mechanical fuel pump doesn't work so well, so the engine has issues starting, so i added an electric pump. At that point it was easy to also add a DPDT relay since I was taking the whole thing apart either way
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Re:Why do they still make car alarms? (2015) by waynesonfire on Tuesday January 19, 2021 @07:20PM (#25840924)
lol, right, sucks when they don't start.
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