A starter relay is the mechanism that controls the connection between your ignition and engine, allowing your car to startup without burning out any of the parts involved. The relay is located within the starter solenoid, which is the part you will need to replace if you need a new starter relay. You can easily perform the replacement yourself, as long as you are careful to remember the layout of your wiring pattern and are patient with all of the steps involved.
Disconnect the battery from your car. This will avoid any surges of power running through the car while you are working.
Pull the command wire off your starter relay. The command wire is the upper most wire connected to the relay and will usually have a colored head holding it onto the upper most relay post.
Loosen the nuts holding the relay in place with a ratchet and socket. There will be two nuts on the relay itself holding the wires in place and one nut right above and one nut to the side of the relay holding it to the inside wall of your car.
Twist the nuts off and pull the wires off the relay posts. You need to remember exactly which wires went on which post and in what order, so mark them or write it down if you have to.
Pull the relay off the car and replace it with the new one. The new relay should be placed in the car exactly as the old one was positioned. It should be aligned just like your old one was.
Put the nuts on the bolts right above and to the side of the new relay and twist them with your hand. Once you are sure it is in place and correctly aligned, tighten the nuts with the ratchet.
Slide the wires onto the posts of the new relay in the exact same way they were on the old one. Refer to any markings or information you wrote down if you can't remember where the wires go.
Slide a washer over the wires on the posts. Your relay should come with these washers and new nuts. Place the relay nuts over the washers and tighten until the washers are pressed up against the wires.
Push the command wires back onto the upper post of the relay and reconnect the battery to the power.
