How to Install a Car Alarm & Remote Entry

Some remote entry systems allow you to start your vehicle before entering it.

A car alarm and keyless entry system can do more than save money on your car insurance and boost your car's value, they are important safety features. Car alarms can stop thieves from stealing your vehicle and valuables, while a keyless entry system can help you quickly enter your car in a foreboding parking lot. If your vehicle didn't come with a car alarm and remote entry, you can install these devices yourself. This job requires some expertise in automobile wiring, however.

Things You'll Need

• Alarm unit
• Key-less entry control pad
• Phone service provider
• Diagram covering the vehicle's specifications
• Paper clip
• Electrical tape
• Support brace or wiring harness
• Wire splicers
• Power drill
• Silicone
• Self-tapping screws
• Wire cutter
• Wire stripper
• 30-amp relays, 2
• 3/8-inch drill bit

Instructions

Alarm Unit Installation

1. Gather all information regarding your vehicle's specifications, including documents outlining wiring codes, locations and varying polarities. You will also need a detailed diagram of your car's electrical system to help locate the relevant parts before beginning the installation process. Call an auto dealer, write to the manufacturer or search the Internet for downloadable copies of these documents. Carefully identify the number of relays, diodes and resistors attributable to the vehicle.

2. Thoroughly study the wiring diagram and the alarm parts side-by-side. Determine which features to install first, such as the keyless entry, starter disable, trunk pop lever or dome light supervision.

3. Gently unplug the metal contacts on the alarm unit. Using a paper clip, press down on the metal contacts to dislodge and eliminate unused wires. Find and match the ends of any given plug. Twist the matching ends of the plugs together and wrap them to each other with electrical tape. Do not wrap all of the matching ends together because each coupled pair serves a different purpose elsewhere for the alarm unit. Wrap all of the harnesses together in electrical tape to create a pigtail comprised of all used wires, which prevents them from fraying.

4. Identify the location of the vehicle suitable to connect the pigtail, such as the driver kick panel, ignition harness or body control modules. Split the pigtail into the chosen vehicle location. Bundle the wires of the chosen vehicle location together. For example, group all of the kick panel wires, ignition harness wires, and body control module wires together. Carefully secure these individual bundles of wire with electrical tape.

5. Inspect the vehicle's door triggers by opening each door and examining whether the dome light or dash light turns on. If the light does not turn on for any of the doors, you may have a faulty door trigger, which could cause the alarm unit to ignore that door. Check the diagram to locate the location of wires underneath the panels that will connect to the alarm unit.

6. Using the proper tools, remove the panels covering the vehicle's wires. Carefully note where each clip and screw goes to avoid confusion when reassembling the panels.

7. Strap the alarm module to a support brace or wiring harness that will mount in a hard-to-see place underneath the panels. Run the valet switch, LED light and external antenna. Using wire splicers, carefully splice and wire any necessary relays first. Use electrical tape to secure the loose ends. Research the steps on checking the polarity of wires before attempting to connect them if unfamiliar with this process. Using wire splicers, splice and connect the remaining wires of the alarm unit to the panel and secure them with electrical tape. Check to see if the connection yields any tension. Carefully readjust the connection as needed until the wires become solid and free of slack.

8. Connect the wire from the alarm unit to the positive siren output. Drill a hidden hole in the firewall and seal a small dab of silicone on the siren wire before passing it through the hole. Thread and pass the wire of the siren through the firewall. Mount the siren to the engine bay and then place the other wire on the ground. Use self tapping screws to fasten the siren to the vehicle by locating a spot on the firewall with an appropriate fitting. Connect the siren downwards to prevent water from seeping in and to echo the sound off the floor for higher amplification throughout the car cabin. Connect the remaining wiring as previously mentioned in other steps.

Keyless Entry Installation

1. Acquire the vehicle's wiring diagram to determine the car's wiring color codes and locations. Find out the type of door locking system and determine the correct procedure to wire door lock relays.

2. Using the diagram, assess which wires to keep and which to eliminate. For example, find an unused channel and shorten the cord to about six inches in length. Use electrical tape to mount the shortened cords to the main harness. Use electrical tape to bundle the rest of the wiring. Leave four inches of wire exposed for each connection end.

3. Reference the wiring diagram to find the car's main power wire, ignition wire, starter wire, and parking light wires. Using wire cutters, remove a small portion of the vinyl covering off the wires that will connect to the key-less entry wires. Use wire strippers to strip the ends of the wires for main power, grounding, ignition switch, parking lights and starter kill. Connect the ends of these wires with the key-less entry wires. Connect the black side of the ground wire to the vehicle's frame.

4. Using the wiring diagram, determine what door locking system comes with the vehicle. Directly connect the keyless system wires to the wires of the vehicle if there's a negative door locking system installed. Carefully wire two 30-amp relays and secure the ends to the vehicle's wiring if there's a positive door locking system or a five-wire reverse door locking system installed.

5. Plug the main circuit board of the key-less entry system into the harness. Test to see if the locks and parking lights work. Using a power drill and 3/8-inch drill bit, install the LED into the dash.

References

• Commando Car Alarms: How To Install A Car Alarm
• Commando Car Alarms: Remote Key-less Entry System