You turn the key, but your Subaru won’t start. Frustrating, right? And it’s even more confusing when the battery is fine. Don't worry, you’re not alone.
This problem happens to many Subaru owners. There could be a few reasons why your car isn’t starting. In this post, we’ll go over the common causes.
We'll also share some simple tips to help you figure out what’s wrong. By the end, you’ll have a better idea of what might be the issue and what you can do about it. Let's get your Subaru back on the road!
Common Reasons Your Subaru Won’t Start Despite a Good Battery
Having trouble with your Subaru not starting even though the battery is fine? It can be frustrating, but there are several common reasons why this might happen. Let’s look at some of them in easy words.
Faulty Starter
The starter is like the car’s alarm clock. It wakes up the engine. If the starter is broken, the engine won’t start, even if the battery is good. You might hear a clicking noise when you turn the key, but the car won’t start.
Bad Ignition Switch
The ignition switch is what you turn with the key to start the car. If this switch is bad, the car won’t start. You might not hear any noise at all when you turn the key.
Fuel System Problems
Your car needs fuel to run. If there’s a problem with the fuel system, the car won’t start. This could be because of a clogged fuel filter, a bad fuel pump, or no fuel in the tank. Make sure you have enough gas and that the fuel pump is working.
Dead Key Fob Battery
Many Subarus use a key fob to start. If the key fob battery is dead, the car might not recognize the key. Try using a spare key fob or replacing the battery in your key fob.
Bad Spark Plugs
Spark plugs help start the engine. If they are worn out or dirty, the car won’t start. Spark plugs need to be checked and replaced regularly to keep your car running smoothly.
Problems with the Security System
Sometimes, the car’s security system might prevent it from starting. This can happen if the car thinks it’s being stolen. You might need to reset the system or use a different key to start the car.
Wiring Issues
Cars have many wires that connect different parts. If one of these wires is loose or broken, the car might not start. Check the wires around the battery and starter to make sure they are connected properly.
Blown Fuses
Fuses protect the car’s electrical system. If a fuse blows, it can stop the car from starting. Check the fuse box and replace any blown fuses to see if that fixes the problem.
Engine Control Unit (ECU) Problems
The ECU is like the car’s brain. It controls many parts of the car. If the ECU is not working, the car won’t start. Sometimes, the ECU just needs to be reset.
Cold Weather
In very cold weather, the engine oil can get too thick, making it hard for the engine to start. Make sure to use the right oil for your car, especially in winter.
Flooded Engine
If you try to start the car too many times without it actually starting, the engine might get flooded with fuel. This can prevent it from starting. Wait a few minutes and try again.
Faulty Crankshaft Position Sensor
The crankshaft position sensor helps the car know when to start. If this sensor is broken, the car won’t start. You might need a mechanic to check and replace this sensor.
How to Diagnose a Non-Starting Subaru with a Good Battery
When your Subaru won’t start, but the battery is good, it can be confusing. Let’s look at how to find out what’s wrong step by step.
Check the Starter
The starter gets the engine going. If you turn the key and hear a clicking noise, but the car won’t start, the starter might be the problem. Try tapping the starter gently with a tool while someone else turns the key. If the car starts, the starter is bad and needs to be replaced.
Listen for the Fuel Pump
Your car needs fuel to start. When you turn the key to the “on” position (but don’t start the car), listen for a quiet hum. This sound is the fuel pump. If you don’t hear it, the fuel pump might not be working. This could be because of a blown fuse or a bad pump.
Check the Fuel Level
Sometimes the problem is simple. Make sure there’s enough gas in the tank. If the fuel gauge is broken, you might not realize you’re out of fuel.
Inspect the Key Fob
If your Subaru uses a key fob to start, make sure the battery in the key fob isn’t dead. Try using a spare key fob if you have one. If the car starts with the spare, replace the battery in the main key fob.
Look at the Spark Plugs
Spark plugs help the engine start. If they’re dirty or worn out, the car won’t start. You can check them by taking them out and looking at them. If they look dirty or damaged, they need to be replaced.
Check the Ignition Switch
The ignition switch is where you put the key to start the car. If it’s broken, the car won’t start. Try turning the key and see if the dashboard lights come on. If not, the ignition switch might be the problem.
Inspect the Security System
Sometimes, the car’s security system can stop it from starting. If you see a security light on the dashboard, try using a different key or resetting the system. Check your car’s manual for how to reset the security system.
Look for Wiring Problems
Cars have many wires that connect different parts. If a wire is loose or broken, the car might not start. Check the wires around the battery, starter, and ignition switch. Make sure they are all connected properly.
Check the Fuses
Fuses protect the car’s electrical system. If a fuse is blown, it can stop the car from starting. Look at the fuse box (usually under the dashboard or hood) and see if any fuses are blown. Replace any bad fuses and try starting the car again.
Try Jump Starting
Even if the battery seems good, it might not have enough power. Try jump starting the car with another vehicle. If the car starts, the battery might be weak and need replacing soon.
Crankshaft Position Sensor
This sensor helps the car know when to start. If it’s broken, the car won’t start. You might need a mechanic to check and replace this sensor.
Troubleshooting Tips for a Subaru That Won’t Start
When your Subaru won’t start, it can be very frustrating. Let’s look at some simple steps to figure out what’s wrong and how to fix it.
Check the Battery
Even if the lights and radio work, the battery might not have enough power to start the car. Batteries can sometimes have enough juice to power small things like lights and the radio, but not enough to turn over the engine.
Try jump-starting the car using another vehicle. Connect the jumper cables from the good battery to your Subaru’s battery, making sure to connect the positive and negative terminals correctly. If the car starts, the battery might be weak and need replacing soon.
Sometimes, the battery connections can be loose or dirty. Loose connections can prevent the battery from delivering power to the starter.
Check the cables attached to the battery terminals and make sure they are tightly connected. If the terminals and cables look dirty or corroded, clean them with a wire brush and a mixture of baking soda and water.
This helps to remove corrosion and ensures a good connection.
Listen for the Starter
If you hear a clicking noise when you turn the key, the starter might be the problem. The starter is a small motor that gets the engine going.
When the starter motor is not working properly, you might hear a single click or a series of rapid clicks. Try tapping the starter gently with a tool while someone else turns the key.
This can sometimes jar the starter motor into working. If the car starts after tapping the starter, it’s likely that the starter is bad and needs to be replaced.
Check the Fuel System
Make sure there is enough gas in the tank. Sometimes, the fuel gauge might not work properly, and you could be out of fuel without knowing it.
Even if the gauge shows some gas, it's a good idea to add a few gallons to be sure. Running out of fuel can damage the fuel pump, so it’s always better to keep your tank at least a quarter full.
When you turn the key to the “on” position (but don't start the car), listen for a quiet hum. This sound is the fuel pump working to pressurize the fuel system.
If you don't hear it, the fuel pump might not be working. This could be due to a blown fuse or a bad pump. Check the fuse box for any blown fuses and replace them if needed.
If the fuses are fine, the fuel pump might need to be inspected or replaced by a mechanic.
Inspect the Spark Plugs
Spark plugs help ignite the fuel in the engine. If they are dirty or worn out, the car won't start. You can check the spark plugs by taking them out and looking at them.
If they are covered in soot or look damaged, they need to be replaced. Spark plugs should be replaced according to your car’s maintenance schedule to ensure the engine runs smoothly.
Check the Key Fob
If your Subaru uses a key fob to start, make sure the battery in the key fob isn't dead. The key fob sends a signal to the car to allow it to start.
Try using a spare key fob if you have one. If the car starts with the spare, replace the battery in the main key fob. Key fob batteries are usually small and can be found at most hardware stores.
Look at the Ignition Switch
The ignition switch is where you put the key to start the car. If it's broken, the car won't start. Try turning the key and see if the dashboard lights come on.
If the lights don't come on or if they flicker, the ignition switch might be the problem. Replacing an ignition switch can be complex, so you might need a mechanic to handle this.
Check the Security System
Sometimes, the car's security system can stop it from starting. Modern cars have security systems that prevent the engine from starting if they detect something wrong.
If you see a security light on the dashboard, try using a different key or resetting the system. Check your car's manual for how to reset the security system. This might involve locking and unlocking the doors or using a specific sequence with the key.
Inspect the Wiring
Cars have many wires that connect different parts. If a wire is loose or broken, the car might not start. Check the wires around the battery, starter, and ignition switch.
Make sure they are all connected properly and look for any signs of damage. Loose or corroded wires can interrupt the flow of electricity needed to start the car.
Check the Fuses
Fuses protect the car's electrical system by breaking the circuit if there is too much current. If a fuse is blown, it can stop the car from starting. Look at the fuse box, usually under the dashboard or hood, and see if any fuses are blown.
A blown fuse will usually have a broken wire or a blackened appearance. Replace any bad fuses with new ones of the same amperage and try starting the car again.
Crankshaft Position Sensor
The crankshaft position sensor helps the car know when to start. It monitors the position and speed of the crankshaft and sends this information to the engine control unit.
If this sensor is broken, the car won't start. Symptoms of a bad sensor include the engine cranking but not starting or starting and then stalling. You might need a mechanic to check and replace this sensor.
Engine Control Unit (ECU)
The ECU is like the car's brain. It controls many parts of the car, including the engine. If the ECU isn't working, the car won't start. Sometimes, the ECU just needs to be reset.
This can often be done by disconnecting the battery for a few minutes and then reconnecting it. If this doesn't work, the ECU might need to be inspected or replaced by a professional.
Starter Relay
The starter relay sends power to the starter motor. If it's not working, the car won't start. The relay is usually located in the fuse box.
You can check it by swapping it with another relay of the same type. If the car starts after swapping the relays, the starter relay is bad and needs to be replaced.
Cold Weather
In very cold weather, the engine oil can get too thick, making it hard for the engine to start. Cold weather can also affect the battery, reducing its power.
Make sure to use the right oil for your car, especially in winter. Using an oil with a lower viscosity can help the engine start more easily in cold conditions.
Flooded Engine
If you try to start the car too many times without it actually starting, the engine might get flooded with fuel. This can prevent it from starting because there is too much fuel and not enough air.
Wait a few minutes and try again. Pressing the gas pedal all the way down while starting can help clear the excess fuel from the engine.
When to Call a Mechanic
Still Not Starting?
If you've checked all these things and your Subaru still won't start, it might be time to call a mechanic. They have special tools and knowledge to find and fix the problem. A professional can diagnose more complex issues that might not be easy to see.
Regular Maintenance
Keeping your car well-maintained can help avoid these problems in the future. Regular check-ups and fixing small issues early can keep your Subaru running smoothly. Regularly check the battery, fuel system, spark plugs, and other components to ensure they are in good condition.
Other Potential Fixes
Checking For A Blown Fuse
One possible reason why your Subaru won’t start is a blown fuse. Fuses protect electrical circuits from overloads and shorts, so a blown fuse can disrupt the flow of electricity. To check for a blown fuse:
- Locate the fuse box, usually found under the dashboard or in the engine compartment.
- Identify the fuse corresponding to the ignition or starting system.
- Inspect the fuse for any signs of damage, such as a broken filament or blackened appearance.
- If you find a blown fuse, replace it with a new one of the same amperage rating.
Verifying The Fuel Pump Operation
A faulty fuel pump can prevent fuel from reaching the engine, resulting in a no-start situation. To verify the fuel pump operation:
- Turn the ignition key to the “ON” position, without starting the engine.
- Listen for a buzzing sound coming from the rear of the vehicle, indicating that the fuel pump is functioning properly.
- If you don’t hear the buzzing sound, it could indicate a faulty fuel pump or a related component. Consider seeking professional assistance to diagnose and repair the issue.
Testing The Alternator
A malfunctioning alternator can cause the battery to drain, leading to starting problems. To test the alternator:
- Start your Subaru and let it idle.
- Using a multimeter set to DC voltage, connect the positive lead to the positive terminal of the battery and the negative lead to the negative terminal.
- Observe the reading on the multimeter. A properly functioning alternator should output around 13.5 to 14.5 volts.
- If the reading is significantly lower or higher, it could indicate a faulty alternator that needs to be repaired or replaced.
Examining The Engine’s Compression
The engine’s compression is crucial for proper combustion and ignition. Low compression levels can result in a no-start condition. To examine the engine’s compression:
- Remove the spark plugs from each cylinder.
- Attach a compression gauge to the first cylinder and crank the engine for a few seconds.
- Note the compression reading on the gauge.
- Repeat the process for the remaining cylinders.
- If you notice significantly low compression in one or more cylinders, it might indicate a problem with the engine’s valves, piston rings, or head gasket. Consulting a mechanic is recommended.
By checking for a blown fuse, verifying the fuel pump operation, testing the alternator, and examining the engine’s compression, you can troubleshoot common issues that may be preventing your Subaru from starting. If these steps don’t resolve the problem, consider seeking professional assistance for a more in-depth diagnosis and repair.
Common Mistakes to Avoid
Jump-starting the Vehicle Improperly
One common mistake that many people make is jump-starting their Subaru improperly. While jump-starting a vehicle can be a quick fix, it’s important to do it correctly to avoid causing damage.
Avoid connecting the jumper cables directly to the battery itself, as this can result in a surge of power that can damage your vehicle’s electrical system. Instead, follow these steps:
- Connect one end of the red (positive) jumper cable to the positive terminal on the dead battery.
- Connect the other end of the red (positive) jumper cable to the positive terminal on the working battery.
- Connect one end of the black (negative) jumper cable to the negative terminal on the working battery.
- Attach the other end of the black (negative) jumper cable to an unpainted metal surface on the engine block of the dead vehicle.
- Start the engine of the vehicle with the working battery and let it run for a few minutes.
- Attempt to start the vehicle with the dead battery.
Ignoring Regular Maintenance
Regular maintenance is essential for keeping your Subaru running smoothly. Ignoring regular maintenance tasks can lead to issues that prevent your vehicle from starting. Make sure to follow your vehicle’s recommended maintenance schedule, which may include tasks such as:
- Regular oil changes
- Replacing spark plugs and filters
- Checking and replacing worn-out belts
- Inspecting and topping up fluids
- Rotating and balancing tires
Not Using The Correct Fuel
Using the correct fuel is crucial for ensuring optimal performance and avoiding starting issues. Subaru vehicles require specific fuel types, such as regular unleaded or premium unleaded gasoline.
Using the wrong fuel can lead to engine problems and may prevent your Subaru from starting. Consult your vehicle’s owner’s manual or contact a Subaru dealership to determine the correct fuel type for your specific model.
Neglecting Warning Signs
It’s important to pay attention to any warning signs that your Subaru may be giving you. Ignoring these signs can result in more serious issues and potentially prevent your vehicle from starting altogether. Some common warning signs to watch out for include:
- Dim or flickering headlights
- Unusual noises when starting the engine
- Difficulty starting the vehicle
- Dashboard warning lights
- Decreased fuel efficiency
By addressing these warning signs promptly, you can avoid more severe problems and ensure that your Subaru starts reliably.
Frequently Asked Questions
How often should I replace my Subaru’s spark plugs?
Spark plugs typically need to be replaced every 30,000 to 100,000 miles, depending on the type of spark plugs your Subaru uses and your driving conditions. It’s best to follow your car’s maintenance schedule or check your owner’s manual for specific recommendations.
What should I do if my Subaru’s key fob isn’t working?
If your Subaru key fob isn’t working, first try replacing the battery in the key fob. If that doesn’t solve the problem, try using the spare key fob if you have one. If neither key fob works, there may be an issue with the keyless entry system that requires inspection by a Subaru technician.
How do I know if my Subaru’s fuel pump is failing?
Signs of a failing fuel pump in a Subaru include difficulty starting the car, engine sputtering at high speeds, loss of power during acceleration, and unusual noise coming from the fuel tank area when the car is running. If you suspect a problem with the fuel pump, it’s best to have it inspected and tested by a professional mechanic.
What should I do if my Subaru won’t start in cold weather?
If your Subaru struggles to start in cold weather, ensure you’re using the correct viscosity of engine oil recommended for cold temperatures. Using a block heater or parking your car in a garage can also help keep the engine warm, making it easier to start in cold conditions.
How can I reset my Subaru’s security system?
To reset the security system in your Subaru, start by locking and unlocking the doors with the key fob. If this doesn’t work, you may need to disconnect the car battery for a few minutes and then reconnect it. Refer to your Subaru owner’s manual for specific instructions on resetting the security system.
What should I do if my Subaru’s engine is flooded?
If your Subaru’s engine is flooded, wait a few minutes before trying to start it again. Pressing the gas pedal all the way down while starting can help clear excess fuel from the engine. If the engine still won’t start, you may need to wait longer or consult a mechanic for further assistance.
