Learn How to Diagnose and Fix a Dead Car.
If you get in and realize your car won’t start, there are different methods you could use to find out which of the many reasons it could be. The first is listening to the sound that comes out when you turn the key.
If you hear just a single click or nothing at all, you may have a bad starter. If you hear a continuous chattering noise, the problem could be the battery. A cranking sound, on the other hand, could be a sign of an issue other than the battery or starter. These are just some of the main reasons a car won’t start.
In the video below and in this post, we’ll teach you how to diagnose a car that won’t start. We will help you identify where the problem is and what you can do about it.
What would cause a car not to start?
1. A dead car battery
2. A blown starter fuse
3. A loose or dirty starter connection
4. A bad range selector switch
5. A seized engine
Diagnose the Reasons A Car Won’t Start
To find out the reasons a car won’t start, you’ll need to test different parts of your vehicle separately. This will help you figure out if you have a bad car battery, a damaged starter, a bad starter connection or wiring, a seized engine, or a bad range selector switch.
How do you check if a car battery is good?
Before taking a look at anything else, you’ll need to first ensure your battery is working perfectly. For this, you’ll need a digital car battery charger.
Follow the steps below to find out if your car needs a new battery. You can also watch the video above.
Step 1: Start by checking the battery connections to make sure they are tight.
Step 2: Connect your digital battery charger and select the right type of battery on the charger’s display. In our case, we had a lead-acid battery.
Step 3: Check to see how much charge your battery has. If it’s low, leave the charger connected to charge it fully. If the battery doesn’t charge well, it could be damaged and you may need to replace it.
How to diagnose a bad starter
Check out the steps below to learn how to diagnose a bad starter.
Step 1: Start by confirming that your test light works fine.
Connect the lead end of the test light to the negative battery terminal and place its tip on the positive terminal. The test light should light up.
Step 2: If your test light works, test your fuses.
Find the fuse box and test each fuse using the test light. Do this while the lead end of the test light is still connected to the battery. Fuses have two openings at the top. Check to see that both openings work just fine.
If the starter fuse or any other fuse is blown, you’ll need to replace it. If the car starts after replacing the fuse, you may still need to go on with your diagnosis since fuses don’t burn on their own. A burnt starter fuse, for example, could indicate a starter that’s drawing too much amperage or a wire that has shorted.
Step 3: Get under the car and locate the starter.
Most vehicles have the starter located near the engine or transmission. This could be on the driver’s or passenger’s side. On this vehicle, it was near the bell housing attached to the solenoid. If you have a front-wheel-drive vehicle, you may find it at the front or up top under the intake of the car.
Step 4: Once you locate the starter, use the test light to check if the power wire is drawing power from the battery.
Connect the lead of the test light somewhere on the vehicle where there’s good ground. This could be on the engine block or transmission.
Place the test light tip on the power wire. You may need to scratch the terminal slightly if it’s dirty or corroded. If the test light lights up, it means that the starter is getting enough power and there’s nothing wrong with the power wire.
Step 5: Test the ignition/signal wire that connects to the ignition switch.
You’ll find the ignition/signal switch right next to the power wire. In some cars, it may go through a relay or fuse. It may also have an end with a stud and a nut. Here, it took the form of a connector that could be easily unplugged.
When testing the ignition/signal wire, don’t connect the tip of the test light directly to the wire. Use a jumper wire and run it to your test light.
Connect the lead end of the test light to the negative battery terminal.
Once done, start your vehicle. If the test light bulb lights up, your ground and signal/ignition wiring are good. This means that the problem is the starter and you’ll need to replace it.
How do you fix a bad starter?
If you determine that your car won’t start due to a bad starter, you can try and bring it back to its working condition. This is especially if you’re in an emergency situation that requires you to move your car quickly.
Find a hammer and have someone try to start the car. Give the starter a couple of hits while the other person turns the ignition key. This helps to jar the brushes within the starter and to allow them to vibrate so as to make good contact. This will hopefully engage the starter and make the car start.
How to check for a bad range selector switch
A range selector switch is an electrical switch that allows your car’s powertrain to determine which gear the transmission is in once you turn the ignition key. It is also referred to as a neutral safety switch.
When it fails, it will not be able to send the proper Park/Neutral position input to the Powertrain Control Module (PCM). And, without this input, the PCM cannot crank the engine when the car is in its Park position.
To confirm if you have a range selector switch that has failed, put your foot on the brake and start the vehicle when it’s in Neutral. Repeat this when the car is in Park. If your car starts when it’s in Neutral but doesn’t when it’s in Park, you may have a bad range selector switch.
How to diagnose a seized engine
Sometimes, your car may not start due to a seized engine. An engine can get seized if it runs low on engine oil or if there’s no oil at all. It could also be caused by overheating, a worn and broken timing belt, or rusted engine parts in a car that has been sitting idle for a long time.
A seized engine is normally characterized by a single knock or clunk sound when you turn on the ignition. The problem will not go away even if you replace the starter or battery. You can follow the steps below to check whether you have a seized engine.
Step 1: Take a socket and breaker bar and place it on the crank bolt. You want to make sure the engine turns.
Step 2: Turn the breaker bar in a clockwise direction. If it doesn’t turn, your engine is seized. Fixing a seized engine will require a professional technician to help restore it to its normal working condition.
Now that we have covered the main reasons a car won’t start, below we have some FAQs to help you with the most common questions our technicians get when it comes to a seemingly dead car or truck.
What is wrong when you turn the key and nothing happens?
If you turn the ignition key and nothing happens, it means your starter motor has failed to turn the engine. This is commonly caused by a bad ignition switch, dead battery, a problematic neutral safety switch, bad starter connection, or a faulty electronic control module.
How do you tell if it’s your starter or your battery?
When you start your engine and hear a click or nothing at all, it could be due to a bad starter. If you hear no sound and have no interior lights, it could be due to a dead battery. A sluggish crank or an inconsistent start are also common symptoms of a dead battery.
What are the signs of a bad starter?
Some of the most common signs of a bad starter include a single loud click or a rapid clicking noise when you try to start the engine, an engine that doesn’t power up at all, the smell of smoke caused by a blown starter fuse, or erratic whirring and grinding sounds.