Remote Starters are becoming more and more common. They are really convenient for people who do not park their car in a garage. With the push of a button, the car can be started. A few minutes later the car can either be toasty warm, with all the windows cleared of ice/snow/fog in the winter, and cool in the summer.

Remote starters should be hooked up to cars with automatic transmissions only! Even though a car with manual transmission can be fooled into believing the clutch is pressed using a relay, if the car is in gear, it would jump hitting other cars or causing personal injury to people nearby. It is illegal in many states to install a remote starter on manual transmission cars.

There are three types of remote start modules:

  1. Stand alone, which includes a remote control
  2. Alarm add-on, which are interfaced to the alarm, and a button in the existing alarm system is programmed to start the car, and
  3. Alarm with remote start included in one module, which is easier and cheaper to install, since less wires are used.


Remote starters are interfaced with the wires at the ignition switch, which control all the main functions in a car. The remote start module basically simulates turning a key in the ignition switch to start the car and keep it running. The microprocessor inside the remote starter module constantly monitors the engine.

Remote starter installations are more complicated than alarm installations. If a mistake is done in the wiring, vital parts of the electrical system could be damaged. If you are not comfortable with tampering with you car’s electrical system, you should have the starter installed by a professional.

Module Placement

An appropriate mounting location for the module is usually close to the ignition switch in a place where wires will not be pinched or cut by moving parts.

Internal switches in the module, such as number of cylinders in the car, running time, light flash, etc, should be set first. All wiring plugs should be connected to the module.

Power, Ignition Wires

Using a voltmeter, identify wires required at ignition switch: Constant power, start, ignition, accessory, extra ignition and/or accessory wires. These are the most critical connections, so it is highly recommended to either use a “T” harness or soldering wires to the factory harness. Main power wires should be fused, in case the module or wiring short out, the car will not be disabled. Always double check connections.

Tach Wire

This is most important wire hooked up to the module. The tach wire gives the module a signal to stop cranking the car once it is running. The most common place to find the wire is at the ignition coil. In some cars the wire can also be found at the instrument panel, or service plugs. Most reputable dealers should be able to get the wiring information from different commercially available sources. Once all the wires are hooked up, check the installation. If the module keeps cranking the car, even after it has started, you do not have the right tach wire.

Some cars that have multiple coils need diodes run to each coil so that the tach sensor in the module works correctly.


Start modules have interrupt inputs for protection:

Brake sensor: Turns the module off as soon as the brake is pressed. The wire can be found usually right at the brake pedal switch, and has (most of the time) a positive polarity.

Hood switch: Usually a negative input. If there is already a switch hooked up to an alarm, a diode should be added to isolate from other switches. This input prevents the car from accidentally starting when the car is being serviced.

Manual disable switches: They immediately disable the module in case of an emergency. Should be mounted in an easily accessible location so that the module can be turned off.

Extra Accessories

Remote start modules usually have extra outputs (either pulsed or constant) that can be used to lock/unlock doors, turn on accessories such as A/C or heater, rear window defroster, etc. Most outputs require relays and building custom interfaces.

Special Cases

Many cars have security protections that require the key to be in the ignition. For example GM cars have a resistor built in the key. This system is easily bypassed by measuring the resistance with a meter, and then adding a resistor to the starter interface. Other cars such as Fords and BMWs have a transponder built in the key. A way to bypass this is by cutting the plastic from a key and mounting it close to the ignition switch, disabling the security system.