How to Install an Ignition Switch on Vehicles

by Contributing Writer; Updated June 12, 2017

The ignition switch on a Vehicles unlocks the ignition lock cylinder and sends an electrical signal to the starter motor so that the Vehicles engine can start. Over time, the ignition switch can fail. Usually, this is due to the tumblers inside the ignition lock jamming. When this happens, you'll need to replace the switch. Once you've removed the old switch, you have to follow a special procedure to install the new one.

Under The Hood:

 How to Install an Ignition Switch on a Harley

Place the new Harley ignition switch on the console, where the old one was. Line up the screw holes.

Insert the four screws and get them started in their holes. Tighten the screws, in a crosswise pattern, turning each screw a little at a time until tightened.

Connect the light/key switch wire to the ignition.

Place the top of the instrument console bolt in the space at the top of the underside of the console.

Slide the console to the install position. Attach the fuel pump connector. Bend the clamp and insert the fuel pump connection into the main harness.

Place the console in position on the fuel tank. Tighten the nut at the top of the console to 50 to 90 lbs. Tighten the Phillips screw and washer that may also be present.

Install the bolt with a flat washer on the rear of the fuel tank. This is on FLHRS models only. This bolt needs to be tightened to 15 to 20 lbs.

Install the new cable strap that came with the ignition. Place the cable strap into the hole on the left of the frame.

Capture the main wiring harness, instrument console connector and the fuel vent tube in the cable strap. Tighten the cable strap. Cut off any excess strap and discard.

Place the battery cable bolt through the battery negative cable terminal and tighten to 60 to 90 lbs.

Install the seat and test the ignition.

Items you will need

  • Torque wrench

  • Ignition switch

  • Owner's manual

  • Phillips screwdriver

 How to Install an Ignition Switch on a Ford Thunderbird

Hold the new ignition cylinder in your left hand and slide the ignition key into the ignition cylinder. The switch is on the backside of the cylinder housing on the Thunderbird.

Turn the ignition key clockwise two positions on the cylinder. The lock should click twice, once for each position.

Insert the ignition cylinder and switch into the steering column in the switch and cylinder input.

Push the cylinder and switch all the way into the column until the ignition switch locks into position on the column.

Turn the ignition key to the "off" position and remove the key.

Items you will need

  • New ignition switch

  • ignition key

 How to Install an Ignition Switch in a 1995 Ford Taurus

Open the hood for access to the battery. Disconnect the negative terminal with a socket wrench. Wait five minutes before replacing the ignition switch. This will assist in depleting the electrical charge in the air bags.

Unscrew the two bolts in the bottom steering wheel shroud with a Torx driver. Pull the shroud down to access the ignition switch.

Unscrew the two screws holding the switch in place with the Torx driver. Pull the switch down from the column. Disconnect the wiring harness from the switch.

Push the wiring harness on to the new switch. Screw it on to the steering column with the Torx driver.

Tighten the steering wheel shroud back under the steering column with the Torx driver. Ensure it is flush with the top half of the shroud.

Connect the negative terminal on the battery with a socket wrench. This will restore electrical power to the car.

Start the car to ensure the switch is working properly. Close the hood and turn the car off.

Items you will need

  • Socket wrench

  • Socket set

  • Torx Driver

  • Torx bits

 How to Install an Ignition Switch on a Scooter

Refer to the wiring diagrams and reference manuals for your model scooter. Confirm whether your scooter uses a 4-pole or 8-pole ignition switch in its electrical system. Purchase the correct replacement switch for your scooter from a scooter dealer or parts shop.

Use a screwdriver to either remove the screws holding the top cover of your scooter headset on, or to release the headlight frame to access the headset inside (it depends on your scooter design). Remove the securing screws and carefully remove the headset top or headlight frame. Disconnect any electrical wiring, making sure to remember what color goes to what connection.

Locate the ignition switch by where it sits in relation to where you insert your ignition key to start the scooter. Carefully disconnect the wiring that goes to the old switch. If you pull too hard, you might strip wires from the connectors. Firmly grab the retaining cap on the outside of the headset attached to the switch. Try to unscrew it by hand.

Use an adjustable wrench and towel if the retaining cap will not unscrew. Hold the switch body with your other hand to keep it still while turning the cap. Pull the cap off when it is loose. Pull the ignition switch into the internal headset cavity, then pull it out.

Remove the retaining cap from your new ignition switch and insert the new switch where the old one was installed. Secure it with the new retaining cap and twist it tight. Reconnect the wiring by color and position to the new switch. Refer to your wiring diagrams if you forgot the correction connections.

Reconnect the headset or headlight assembly and secure them with screws again, using the Phillips screwdriver. Insert the ignition key into the new switch and test that it works properly, connecting electrical circuits and then allowing the scooter engine to start.

Items you will need

  • Wiring diagrams for your model scooter

  • Replacement ignition switch

  • Phillips screwdriver

  • Adjustable pliers

  • Shop rag

 How to Install an Ignition Switch on a Chevrolet Pickup

Open the hood and disconnect the negative cable from your truck's battery.

Remove the covers from the steering column by removing the screws from the bottom cover; the upper cover should come right off after the lower one. On some models, you must also remove the driver's side knee bolster.

Disconnect and remove the park lock switch from the lock cylinder housing; this is needed on some mid-size trucks like the Colorado. Disconnect the lock's electrical connector, and depress its tab with a small screwdriver to release the switch.

Insert the key, and turn it to the "On" or "Run" position. On some mid-size models you must turn it the other way into the "Accessory" position. Insert the retainer pin into the hole in the lock cylinder, and pull the cylinder out of the steering column.

Disconnect the electrical connectors for the ignition switch from the cylinder--there can be one or two of them, depending on the model, and one of them can require twisting. Then remove the switch from the cylinder by pulling out its screws.

Screw the replacement switch in position on the lock cylinder, and connect its wiring harness (or harnesses) to the electrical connector(s).

Insert the lock cylinder in the same position it was in when you removed it, aligning the lock's retainer with the slot in the steering column housing. Press the cylinder in until the retainer activates.

Replace all other components in reverse order of removal.

Items you will need

  • Small screwdriver

  • Ignition key

  • Electrical ignition switch