If you wish to install a remote engine start in your vehicle you must note that most vehicles in today's market are equipped with a factory installed security device that prevent your vehicle to be started without the correct code (ignition key must be present), it either has an Immobilizer (Transponder) or Data-Bus (e.g. GM Passlock System)  or combination of both, Also, the Doorlock system in your vehicle may not work with a Doorlock Output from aftermarket security system or remote engine start. The modules we offer are the latest state-of-the-art interfaces which eliminate the guess work of which Remote Start By-Pass you will need, most of our By-Passes Modules do not require a second key for the modules to work properly. Under the vehicle make you can locate the year and model of your vehicle and we'll do the rest for you...