car alarm remote hard wired to the car ba

Printed From: the12volt.com
Forum Name: Car Security and Convenience
Forum Discription: Car Alarms, Keyless Entries, Remote Starters, Immobilizer Bypasses, Sensors, Door Locks, Window Modules, Heated Mirrors, Heated Seats, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=89962
Printed Date: May 09, 2025 at 3:39 PM

Topic: car alarm remote hard wired to the car ba

Posted By: mikeh500
Subject: car alarm remote hard wired to the car ba
Date Posted: February 02, 2007 at 10:58 PM

Ok so I bought an AutoLoc/ Stellar alarm and shaved door kit. Its two components, the alarm control unit and the add on 18 channel control unit to control the doors along with what ever else I wire up. I've go the two units wired up and working but I don't want to carry two remotes. The instructions for the kit say you can wire a relay up to leads soldered to the remote switch and control the remote buttons with a channel on the add on unit. I want to do this but I don't want to worry about the battery in the "wired in" remote going dead. The battery for the remote is an A23 12V battery (data sheet on the battery). My car battery is 12V, why not wire it to the car? So here's the delima... I soldered leads to the battery post of the remote and tested it using the car battery, it works. I soldered leads to the button on the remote and tested it with the car battery, it works. I wired the switch leads to a relay switch and triggered the relay with the old remote battery, it works. I wire the remote to the original remote battery and trigger the relay with the car battery, it works. I wire the relay to the car battery and the remote to the car battery and it fries the button and that button will no longer work. I've tested this on three buttons so far and it happens that way every time. WHY? I don't get it... What am I missing?

Pictures of the front and back of the remote.

Front
posted_image

Back

Hi rez front Hi rez back

Replies:

Posted By: mikeh500
Date Posted: February 02, 2007 at 11:17 PM

Oh, by the way I believe it is the black microchip on the back that fried.

Posted By: mikeh500
Date Posted: February 03, 2007 at 9:07 AM

I think I'm going to try putting a diode on the relay and some resistors on the lesds attached to the circuit board. Maybe that will keep it from frying.?

Posted By: duct tape
Date Posted: February 03, 2007 at 10:33 AM

car batteries rest at 12.6 volts, most cars charge at 14.4 volts. maybe the excess voltage is frying your remote.

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Posted By: mikeh500
Date Posted: February 03, 2007 at 10:43 AM

I haven't tried it while it was running but I don't think the extra .6 volts is doing it. If it were I would think it would do it any time not just when using the relay wired to the car and the remote wired to the car. Thanks for the help though!

Posted By: duct tape
Date Posted: February 03, 2007 at 11:18 AM

sorry, i missed the part where you hooked it directly and it worked posted_image

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Posted By: mikeh500
Date Posted: February 03, 2007 at 1:26 PM

Ok, I think I got it. I put a diode between the 12v power to the relay and the neg signal to the relay. Put another one on the pos input side of the remotes switch and a 330ohm resister on the output side of the switch. It hasn't fried yet, the other buttons fried with one try, and I've given this one around 50 so far. Hopefully it will keep it up.