Electrical Door lock security issues

Jan 12, 2021
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Nh
Been trying to setup my 1988 gt vert with a compustar security system for a few days, I know nothing on automotive wiring and took on this project car to learn about them, I have been working on the door locking part of the system and had to reverse polarity because the supplied power is negative. (Pic below) I wired to these connections using a temporary setup and the locks worked well on the keyfob however the door locks were underpowered using the door switch. I started to splice wires for permanent use but I keep popping my 12v constant fuse going to my relay using the keyfob and if I connect my grounds together on a ground screw and hold the door switch my wires from the relay start to heat up instantly, my car is completely open right now so I can splice wherever with ease. Any help is greatly appreciated .
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90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
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You have to wire in 2 additional relays because the ford system reverses polarity on the wires to lock and unlock. All the ford systems work the same pre 94 with power locks. Try googling it on the interwebs. Might find it under adding keyless entry to 92 crown vic.

I've done a lot of keyless entry and alarm systems on all types of ford's. Can't remember how the two relays got wired because it's been over 20 years. I've spent those 20 years ripping the alarms out of Fords and putting them back to factory. There will be 4 added failure points that could cause your door locks to not work. In a couple years the remote, alarm brain, relays, or wiring connections will fail.

Now, I only install kill switches and horn triggers from the accessory wire, dome lights, and under hood pressure switch. Very easy and reliable without the added failure points.

My favorite are the trackers from Amazon. I like to catch the thief, not scare him away. This way they learn their lesson.
 
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Jan 12, 2021
17
1
13
20
Nh
Figured it out the locking motors use the lock side as a ground when unlocking and vise versa so I wired ground to the switch and power going to the motor and it works, it may br different for other relays, i used one from firstech the goes directly to the security computer. Now Im wiring my camera system and setting up for my new stereo once I find one I want.
 
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