Step 16: Turn on ignition if using a switched power source. Test the switch. I like using an illuminated switch, because I know that the switch is working, so if the locks aren't working, I know the switch is not the problem. When you engage the switch, you'll hear a click come from the solenoids if they're working. Make sure the sound is coming from both sides. Once you've got that working, put the interior back together.
Step 17: Bleed the brake system. Start with the passenger's rear wheel, then the driver's rear, then the passenger's front, then the driver's front. Make sure you have all air out of the line and top off the brake fluid after every wheel. I've also heard of people losing pressure in the brake system due to an ill fitting OEM master cylinder cap. I went around the threads on the master cylinder a couple of times before replacing the cap for the last time, to make sure I've got a good seal. ABS systems are very sensitive to air. While bleeding the brakes, make sure to check for any leaks and address those if needed.
Step 18: Find a suitable, off-road, location to test the line locks. Firmly depress the brake pedal and engage your switch. If using a momentary switch, keep it depressed. Release the brake pedal. At this time, only the front brakes should be locked. When you are finished, release the momentary switch (or turn the rocker switch off) and your front brakes should release.
If your line locks are not working, try the following:
Double check your grounds
Check the add-a-fuse. Make sure the fuse is not blown and the assembly is oriented properly
Make sure all lines are attached properly and there are no leaks
Double check all of your wiring
Disclaimers: Line locks are intended for off-road use only. StangNet and its staff do not condone the use of off-road products on the street. If you are unfamiliar with ABS systems or electrical wiring, do not attempt to install without a trained professional. Improper installation or use could lead to death. Install and use at your own risk.