When you have a remote car starter you can start the engine from outside the car or turn it off in an emergency, but these devices aren't infallible. The article below will go over how you can troubleshoot a remote car starter.
A remote car starter is connected to the battery. This is how it starts the engine. If the battery is low on power it won't work. When the car is off, turn on the lights and if they are dim, or don't light, the battery power is low. You can also use a voltmeter to check the leads. A dead battery is under 11.8 while a full battery is 12.5 volts.
If the ignition switch is faulty, the remote car starter won't work properly. Start your vehicle. If the dashboard lights turn off, rather than simply dim, this indicates a problem with the ignition switch.
The solenoid is between the battery and engine and is connected to the car starter by a series of braided wires. Use the negative lead from the voltmeter and touch the metal car frame. Place the positive from the voltmeter on the solenoid's wire. It should register 12.5 volts otherwise it is not working properly.