Stupid GEM Module on Fords

HELP!!!
If I'd had a stick of dynamite today I wouldn't have a truck or an alarm anymore! All of the features of my alarm are working great until it remains armed and unattended for about an hour and then the alarm blares. I talked to the manufacturer of the alarm and they said to diode isolate the negative door pin triggers on my 2000 ford ranger. The problem is, I already have and the stupid thing still triggers the door pins!! Any suggestions?

Thanks Gene

yr make and model of car............

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Good Luck
David
Ace Security
813-376-9778
Tampa
Donate to the 12volt

* Ford's G.E.M. May Drop A Low Signal Across The Dome Light And In Most Cases Cause A False Trigger. To Eliminate This Cut the Door Pin Trigger Wires At The G.E.M. And Insert A One-Amp Diode With Band Side Faceing Doors.Make Your Isolated Connection On The Door Pin Side. The GEM (Generic Electronic Module) is to the left of the radio.Door Pin Wires:YELLOW/BLACK (DR), GRAY/RED (PS)

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Good Luck
David
Ace Security
813-376-9778
Tampa
Donate to the 12volt

this the info that i have:


***Dome Light:Ford's G.E.M. Will Drop A Low Signal Across The Dome Light And In Most Cases Cause A False Trigger. To Eliminate This Cut the Door Pin Trigger Wires At The G.E.M. And Insert A One-Amp Diode With Band Side Faceing Doors.Make Your Isolated Connection On The Door Pin Side. The GEM (Generic Electronic Module) is to the left of the radio.

are you cutting the wire at this location???

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Good Luck
David
Ace Security
813-376-9778
Tampa
Donate to the 12volt

I did not cut the door trigger wires instead I used a T tap connection and then connected the diode cathode(stripe) to it and the anode goes to the alarm.  This should work the same unless the diode is supposed to be placed in series with thw existing circuit.

wrong


wrong


first of all your alarm has to have double pulde unlock and this is simple


take the unlock wire from alarm brain and two diodes.

find the drivers side pass door trigger wire.
as well as unlock wire from car. then using diodes connect the unlock wire to both the unlock wire of car and the trigger wire. after that set alarm to double pulse unlock. now check it out simple. close doors (leave windows open) and press the last two keys on the drivers door this will lock all doors . wait five minutes then reach your hand in the door and press the unlock switch if nothing happens this is good that means the gem went to sleep. now press unlock on the after market alarm and wait cause the first pulse will wake up the gem and the second pulse will unlock the doors. so it take about two to three seconds to actually unlock the doors. if this works then close it up your done. if not check to make sure the alarm is sending two pulses when you press the unlock button. also if it does not work do this alow it to remain sleeping . and press the unlock button once then again within 2 seconds this should unlock the doors if it does that mean either you did not set alarm to double pulse unlock or it does not have it in that case you will have to get a pulse generater from dei. if your using a dei alarm it is menu 2 section 10

to access it with a dei alarm
turn key on to on poss and then back off.
press valet and hold until you hear one beep and three seconds later another then press and release valet 11 times on the 11th hold it and wait for the ten beeps from siren and or ten flashes from led continue holding valet and press the unlock key on remote once. than let go of valet and turn key on then back off, you dont have to go to the gem for anything.


thats for locks

now for door triggers you have to double diode each trigger. this will only allow the negative to come from the door and not the gem,. yes it does sound out a pulse . double dioding does the same thing as if you went to the gem but it is alot easier . just double diode the trigger that means two diodes on each door trigger. since it is neggative.   take the two diodes and the side with the stripe twist it together and use a butt connector and connect the twisted side of diodes to the door trigger make sure it is the door trigger it self and not the side of the wire going to the gem. then take the remaining side of diodes and connect on the other side of factory wire
(gem side) and the other in chain to the after market alarm brain do the same for each door test and you should be all good.

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Jon
Installer/Help Technician
---coral springs florida---
mecp certification is not always needed. I have it and it has not helped me out at all. my experience out shines it.

Thanks, I think i got it now.  Before I was under the impression that the pulse the gem sends was a positive one and not negative.  I wish I could find an actual schematic diagram a line diagram for this car, that way it would be alot easier.

I am having a tremendous problem getting this setup to work in a 2003 Ford Expedition. The door switches in this vehicle show a ground when the door is closed. This is reversed from what I am used to. Any ideas? The keyless module in the unit is on the passenger side. I don't think it has a GEM that works the same way, because I am using a one pulse unlock and it works fine. Even the vehicle is left overnight.

Use this diagram and use the first diagram.

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Jeff
Velocity Custom Home Theater
Mobile Audio/Video Specialist
Morden, Manitoba CANADA

Jeff,

Thank you for the information. One question though. The setup in the diagram will result in the relay being active anytime the doors are closed. This 2003 Ford Expedition door swtiches show a strong ground when the door is closed (not open) and between +5 to +9 volts when the door is opened. The diagram you provided doesn't seem applicable to this situation as the switching to ground is reversed from the normal convention. I tried diode isolating all of the connections and tried using a positive trigger, but it is not strong enough to trigger the alarm consistently. I need some way to take the ground when the door is closed and convert it to a ground when open signal. Any ideas on how to make this work in the 2003 Expedition would be greatly appreciated. Isn't there one wire somewhere in the vehicle that sends a signal to the dome light circuit to let the vehicle know that the door is open?