negative pulse wiring in a code alarm
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=94828
Printed Date: April 26, 2024 at 9:55 AM
Topic: negative pulse wiring in a code alarm
Posted By: Fosgate3
Subject: negative pulse wiring in a code alarm
Date Posted: June 15, 2007 at 7:13 PM
I could have sworn that I made a post about this earlier but it's not here now so here goes again: the car is an 07 Saturn Ion3, the alarm is a CodeAlarm CA670. on the alarm, there is a small 4pin harness. among the wires is a blck/red wire that is to give a negative pulse signal when the remote start is deactivated. This wire would be used for locking the doors back after the RS is turned off via the remote and the factory system unlocks the doors b/c the ignition is lost. It could be used also to give a neg pulse to the door pin switch so that the accessories turn off after the remote start is deactivated via the remote. the thing of it is, is that the installation manual does not indicate how to connet this wire and what to connect it to in order to get it to perform these things. I was wondering if anyone else used a code alarm and if anyone knew what to do. I know the factory keyless cna be programmed to not unlock after the ignition is turned off but I like the idea that the car unlocks the doors for me, especially since the locks do not unlock when you pull the door handle. So, I'd like to keep that aspect of the factory system and would prefer the code alarm to do what's needed. Hopefully this post will stay up here. thanks!
Replies:
Posted By: Fosgate3
Date Posted: June 15, 2007 at 8:25 PM
I went out and just for the sake of "seeing what it will do", put the neg probe of the DMM to see what the blk/red wire does. It read and maintained a full negative signal through arming, remote starting, and disarming. It makes me wonder if the other three wires have to be connected as well?
Posted By: peterubers
Date Posted: June 15, 2007 at 11:05 PM
sounds like that BLACK/ red wire is a status (-) output wire ... is the 4-pin harness for a bypass module? Usually there is a 12 volt red wire, a black ground wire, and a multicolored status wire in the bypass harnesses off r/s brains... sounds like this may be similar?
-------------
The search function is your friend.
Posted By: Fosgate3
Date Posted: June 16, 2007 at 9:26 AM
per the install manual (page 18 and downloadable in the downloads section of this site), the 4pin harness used on the alarm is called "4 Pin Remote Start Pulsed Outputs". There are, of course, 4 wires, all 500mA, neg pulse. The first does a factory disarm/pulse before shutdown (lt.GREEN/ blk); the second does pulse after start (lt. blue); the third does pulse after shutdown (blk/red--the one I feel that I need to use); and the fourth is pulse during crank (blk/yel). So, whatever that tells you... I know I could leave the RAP system going if I chose to turn off the remote start via the remote as the RAP system is timed. I prefer not to but that's okay. The doors unlocking after the RS is shut down via the remote is a little more of a concern. I sorta got this problem solved by reprogramming the factory system to *not* unlock after the ignition is turned off. This works and solves the problem but now, when I park the car, I have to press the unlock button in order to get out as the door handles do not operate the locks like they do in many other chevy/gm vehicles. In regard to this, I noticed a programmable feature with the Code that unlocks with ignition, and I'm assumingthis means "unlocks when ignition power is off" as is the case with the factory system. If anyone knows a better way to do the RAP system and the lock/unlocking thing I'm facing, please, by all means, post : )
Posted By: swamprat323
Date Posted: June 16, 2007 at 11:32 AM
if doors are unlock after shutdown then use the "pulse after shutdown" to lock the car. program the code to igntion lock and unlock so when u turn the car off to get out the doors will unlock.
Posted By: Fosgate3
Date Posted: June 16, 2007 at 12:06 PM
As for the programming the code to do the lock/unlock after ignition, that's what I thought I needed to do (was told otherwise elsewhere). Now, with the pulse after shutdown wire... where does that get wired into? logically, I'd think the lock wire of the alarm going to the relays. However, when I tested this yesterday, nothing happened. I used my DMM on this wire and found that it is a constant negative signal, not pulsed.
Posted By: swamprat323
Date Posted: June 16, 2007 at 12:22 PM
yea it go to the lock wire in car you may or may not need relays. just tie it into the door lock harness of the code system. you car has negative locks and your code don't have on board relays.
Posted By: dualsport
Date Posted: June 17, 2007 at 9:43 AM
Fosgate3 wrote:
However, when I tested this yesterday, nothing happened. I used my DMM on this wire and found that it is a constant negative signal, not pulsed.
When you test that signal, get a 1k resistor and connect it between the output and a 12V source, then see if it pulses to ground when activated.
I don't know the specifics of your alarm, but it may be what's called an open collector output, which is pretty much like a switch that opens and closes to ground, and doesn't supply 12V when it's off. If you don't have anything else on the line pulling the voltage up, your meter won't see 12V when it's off. That may be why you didn't see any change whether the output was on or off.
By testing it using a resistor to pull up the output when the switch is open, you should be able to see it change when the switch closes and grounds it. The resistor is needed for this test to limit the current that is drawn by the switch, if you directly connected it to 12V, it'd overload your output and blow it out.
You said you connected the neg probe of your meter to the output; did you connect the pos probe to 12V? That would also be a way to check it; if you did it that way, it should have worked.
|