Looks like the added feature is the SST (spread spectrum technology) 1 mile range -- same as they use w/ viper remote starts and other DEI brands.
If you can spring it... go for the range, it's a one time deal, and you'll thank yourself later that you have the added range.
As far as testing each wire with a voltmeter:
1) obtain a digital voltmeter from an auto store, home depot, radioshack, etc.
2) place the black lead into the com port and red lead into the "V" port
3) switch the multimeter (i.e. voltmeter) to 20 vdc, properly ground the black lead (I used aligator clips to ensure that the lead does jostle loose from ground during the testing of all my wires).
4) touch the red lead to the wire you're intending to test. Usually these multimeter leads have spiked ends so you can often get away with probing a wiring harness with the red lead and determining the wire charge (+ or -). Make sure you securely have the red lead touching the wire of interest while you test the function that it utilizes (i.e. if you're testing a doorlock wire, make sure the red lead is securely touching the intended wire as you press the doorlock button).
For wires that don't allow you to easily probe the exposed metal in the wiring harness, you can strip a little of the wire in-line and test the wire in that fashion. Just be sure and tape off the stripped portion of the wire if you determine that you've found the wrong wire.
Work in this order: 1) do all the ignition harness wiring first (12 volt constant, starter, ignition, accessory wires (some vehicles have more than one of each)) as well as the horn and parking light output and tachometer wire, system ground wire, and brake wire.
** Next you much tach learn or voltage learn the system (voltage learn if you've opted to use "voltage sense" vs. tach learning the remote start brain. It's highly recommended that you TACH learn it ... rather than voltage sense.**
*** now test the remote start function only; and if you have an immobilizer, do not install this just yet, just place a key in the ignition barrel but do not turn. ***
*** if the remote start is able to start the car appropriately, then the next thing to do is install the immobilizer bypass ***
2) Do the alarm/doorlocks next
3) do accessories, such as trunk, defroster, heated seats
4) Program the remote start brain for any special features, alarm settings, siren settings, etc.
5) re-test the entire system (remote starting, doorlocks/alarm, trunk, accessories)
6) start consolidating wire bundles and looming them and taping them off and/or zip tie-ing them. Loom any wiring in the engine bay, use grommets for holes you've made in the firewall to transport wire across it.
7) pack all of it into the lower dash, test again, verify it's working.
8) mount your antenna, hide the excess wire behind the A-pillar and the interior headliner along the upper windshield edge.
9) re-test for range now that the antenna is mounted
10) secure brain under dash, replace mouldings/lower dash materials -- finalize the project
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