Easy Installs: Car Alarm Wiring Guide

Car alarm wiring can seem to be an insurmountable problem to the uninitiated. However, as long as you can perform an Internet search, you should be able to find a chart or diagram that will help on your do-it-yourself (DIY) alarm install project. At the end of this article a link to a sample wiring diagram for a remote start security system is included.

Tools and Materials Needed

• Connectors (both crimp-type and inline taps)
• Multimeter
• Wire strippers/crimpers
• Drill with 1/8 and 1/4 inch bits and a screwdriver tip
• Self-tapping screws
• Rubber grommets (2 for routing wires through the bulkhead)

Steps

1. Identify wiring system. Lay out your new alarm system and study the alarm wiring diagram supplied with the unit.
2. Decide mounting location for control unit. Many installers will put this under the dash and route the antenna up a door pillar. Others will mount this in the trunk in order to confuse potential thieves. If mounting on a metal piece, use the self-tapping screws to secure the unit. Route the antenna wire so it is as high as possible.
3. Determine door switch polarity. Carefully remove the plastic trim panels from the door pillars and locate one of the switches. Use the multimeter to determine if there is a path to ground with the door open or closed. You will need this when wiring the contacts.
4. Route power and horn wiring. Typically you can tap power for the unit off of your fuse box. Either carefully drill a hole in the bulkhead and insert a grommet, or find an existing hole and route the horn wires to where you wish to locate the horn.
5. Connect doors and locks. Using the charts and diagrams linked to, locate the proper wires for alarm triggers and door locking and unlocking, and make the necessary connections.
6. Fasten accessories. If you plan on a trunk release, locate those wires using the supplied links and make the required connections. Mount and connect any accessories such as glass breakage detectors and shock sensors, and make the necessary connections.
7. Connect horn and power. Mount the horn using the self-tapping screws and make the required connections. Connect your ground wire to complete the power circuit and test your alarm.

A sample security and remote starter diagram can be found here. A site that will supply you, in chart form, with the required wires and basic locations can be found here. Be sure to fully read the installation instructions that came with your alarm system before attempting this project.