By an Autoloc system. They are easy to install. All of the wires have connectors on them. All you do is mount the actuators and plug all the wires in. The system also has a lock/unlock inputs for a aftermarket keyless/alarm system. I just installed that kit and is was a snap. Total installation time was a little over an hour for the power doors and power trunk kit including wiring to my keyless alarm. You can check out my install at
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