How Does My Car Starts On Its Own Without Key?

Imagine walking out to your car one morning and finding it running. The doors are unlocked, and it was sitting idle. Isn’t it scary and treat to burglars? In this post, we’ll look at how the car starts on its own without key and how to fix it.

Maybe the wires for the battery terminal on the ignition switch have been switched with the wires for the starting terminal on the ignition switch, causing your starter to engage. This would only occur if the original wiring was tampered with or if the remote starter was installed incorrectly.

How Does My Car Starts On Its Own Without Key?

engine

The most likely cause is power short on a wire coming from the ignition switch or going to the starter. This indicates that the relay is receiving power and transmitting it to the starter, or that the starter is receiving power from a short past the relay. Finally, this could be a shorted relay.

1. Problem In Starter Motor-

starter

The most likely cause is power short on a wire coming from the ignition switch or going to the starter. This indicates that the relay is receiving power and transmitting it to the starter, or that the starter is receiving power from a short past the relay. Finally, this could be a shorted relay.

Checking power at terminals 3 and 5 of the starting relay is an easy approach to narrow down the problem. If there is no power at terminal 3, there is a short between the relay and the starter on that wire. Replace the shorted wire or have it professionally repaired if there is a spliced wire. If the starter relay is welded shut, you may need to replace that as well.

2. Short-circuit In Fuse Box-

Premium Photo | Close-up fuses in fuse box inside the car.

Fuses are used to even out and reduce the electrical current that flows through wires to protect electronics from being damaged by too much electricity. A rectangular fuse is made up of two push-in connectors connected by a fuse wire enclosed in a protective covering, which is typically made of plastic. If a fuse in the fuse box fails, the car will start without a key. Because of the havoc caused by the electrical short in the fuse box, the car mostly starts on its own without the key.

3. After-Market Accessories-

after market

There are accessories available on the market that help to modernize the car. Most owners of older generation vehicles choose these accessories to keep up with the modern world. What they don’t realize is that using cheaper car accessories can quickly turn into a nightmare for them. Poorly installed car accessories to remortgage or modernize the vehicle can cause it to start on its own. A cheap car component has no solution or fix. Avoid installing such items at all costs.

4. Corroded Or Broken Wiring-

Damaged or dirty wires to the battery or the starter solenoid (or loose wires) can cause a short circuit in the starter leading to starting the engine by itself

How To Stop Car Keeps Turning On By Itself?

We will recommend you to try these methods which may cause your vehicle to startup

1. Replacing Ignition Switch

ignition

Unless the key is in the III position, the starter solenoid should NOT be charging the starter to turn (start position). Our best guess is that the ignition switch has failed and must be replaced.

We have quick instructions so you can replace it easily

1. Using an Allen wrench, remove the Cover.
2. Remove the collar that is wrapped around the steering wheel.
3. Disconnect the ignition switch.
4. Unscrew the two screws that secure it to the steering column.
5. Install the new one by plugging it in.

We will recommend you watch the tutorial before servicing-

2. Replacing Starter Motor-

Before replacing the starter motor inspect the location of the starter by checking the OEM manual and its build and make –

Step: 1 Jacking Up The Car

Remove the battery. Only the negative cable must be removed. Also, raise the car to allow simple access to the parts.

Step: 2 Removing Terminals And Wirings

wiring

Remove the terminals from the battery and remove the wiring harness to the starter

Step: 3 Removing Bolts

Remove the retaining bolts from the starter. Take out the starter. This can help you confirm that you are working on the relevant car problem.

Step: 4 Removing Starter

starter motor

Remove the old starter with caution, being careful not to damage any other components. Transfer any heat shields and/or brackets to the replacement starter (if equipped). Then compare the size of the new replacement with the old one, as well as the make and model of the car for part verification

Step: 5 Replacing Starter

starter

Examine the flywheel teeth for wear. Put the new starter in place of the old starter. If necessary, keep the starter shim in mind. Tighten the starter retaining bolts evenly and securely. IMPORTANT: Do not overtighten. Connect the wiring to the solenoid starter. Replace the battery and restart the engine. It may end the problem leading to the car starts on its own without key

Video Tutorial

We recommend you watch the tutorial for easy understanding-

What Is The Cost Of Replacing The Parts?

A new starter may cost between $80 to $350, but you must also consider labor fees, which can range from $150 to $1,000. The cost of a complete starter replacement for most vehicles is around $500, while the cost of an ignition switch is between $70 and $300. What exactly is this? Expect to pay between $60 and $180 in labor to replace the switch.

Conclusion

If your car starts on its own without a key, this can be a serious problem. Carjackers may target your vehicle as a potential target for theft. A car with a manual transmission may also begin to roll forward and cause an accident. Finally, electricals can cause a fire. This problem can be dangerous since it can lead to theft and harm to life and property, therefore it is best to remedy the issue as quickly as possible.

Happy Driving.

Leave a Comment