14 Symptoms of a Bad Ignition Relay

symptoms of bad ignition relay

The ignition relay in your vehicle is one of the most important electronic relays that’s found on the fuse box. This is located inside the engine compartment under the hood and it provides power to the ignition system and the fuel system. When you turn on your car, you don’t have to turn on the car fully, you can only turn on the car’s ignition along with the other devices like the lights and the stereo.

When your vehicle turned to the on position, the relay sends power to the vehicle’s ignition and the fuel systems components. This includes the ignition coils and the fuel pump. If there’s a problem with the ignition relay, it can cause a lot of failures in the vehicle and since the ignition is an important system, this can be bad for your vehicle. You can sense when the ignition relay is failing because it won’t turn on – you’ll notice that none of the lights on the dashboard come on.

What is the Ignition Relay?

The ignition relay is an electrical motor that sends power to the ignition so that your vehicle can turn on – this includes things like the dashboard lights, the horn, stereo, charging ports, windscreen wipers, and vehicle lights. The ignition relay also helps to provide power to the fuel system, and this happens as soon as you turn on the ignition using the key. Once your key is turned, the ignition relay is switched on and power is sent to the systems so that your vehicle can function properly.

Power is then sent to the ignition coils so they’re ready to send electricity to the spark plugs when you turn on the engine. When you turn on the engine, fuel is then sent from the fuel injector and oxygen is sent to the intake manifold so that the air-fuel mixture is made. Electricity from the ignition coil is then sent to the spark plugs to create a spark for the air-fuel mixture to be ignited in the cylinders so that the engine can start – this process happens very quickly.

Since the ignition relay is powered by electricity from your vehicle’s battery, it’s meant to last as long as your vehicle lasts – components and relays inside the fuse box aren’t really exposed to wear and tear so it’s rare for them to get damaged. However, in rare cases, the ignition relay can fail because of water exposure, damage, an accident, or wear.

If your ignition relay is bad, no power will be sent to the ignition coils and the fuel system. Therefore, your vehicle could end up stalling, the battery could be drained, or the dashboard lights won’t come on. The worst thing that can happen because of a bad ignition relay is that the engine fails because the spark plugs don’t have enough power to send electricity to the ignition coil.

Ignition Relay Fuse Location

The ignition relay is located inside the fuse box in the engine compartment under the hood. The fuse box is a long black box that contains the ignition relay as well as all the other relays. It’s unlikely that you find the ignition relay anywhere else in your vehicle but it’s still possible. The fuse box usually contains a diagram that’ll help you locate the ignition relay. If you’re unable to find it here, you’ll need to check out your vehicle’s service or repair manual. If these are no longer available to you, you’ll need to consult with a mechanic.

Symptoms of Bad Ignition Relay

There are a few symptoms that’ll let you know the ignition relay is bad and these symptoms can relate to other damaged components or just the ignition relay itself. The first thing you should do is inspect the ignition relay in the fuse box in the engine compartment under the hood. Make sure to look for signs of damage and for any dirt that could be disturbing the functionality of the relay. This is a common reason why the ignition relay could fail so make sure that there’s no dirt near or on the ignition relay. The car battery can also damage the relay due to inconsistent flows of electricity to it. Down below are all the symptoms that will let you know you have a bad relay.

If you want to know if your relay is bad for certain, you can use a professional OBD2 diagnostics tool (View on Amazon) to help you find this out. Whenever there’s a problem within the engine compartment, an error code is sent to a computer within your vehicle called the Engine Control Module. Using a professional mechanic OBD2 diagnostics tool, you can plug it into your vehicle and it’ll intercept all the error codes stored in the diagnosis system in your vehicle – you can then use it to check what the error codes mean and see if any of them are being caused by a faulty relay.

If you don’t use a professional tool, you’ll have to look up what the error codes mean by looking at the service manual or search online for what they mean. If you’ve found out that the ignition relay is failing, you’ll need to replace the ignition relay (View on Amazon) – it’s also cheap and easy to install – you simply have to plug it into the fuse box.

1. Ignition Unresponsive

Since the ignition relay sends power to the ignition, when you turn it on with your key, if the ignition is unresponsive, this will indicate that the relay isn’t working properly. All the ignition does is get the vehicle ready for start up – it gets the fuel pump and the starter ready so the engine can start up.

If you notice that the lights don’t come on or any other devices don’t come on when you turn on the ignition, it’s an indication that the relay is failing. It’s important that the relay works properly in your vehicle because you won’t be able to drive your vehicle if not – the ignition coils can’t be given any power, therefore, the spark plugs can’t ignite the air-fuel mixture.

2. Engine Stalling

If you notice that your engine is stalling, this can indicate that there’s a problem with the ignition relay. When the engine stalls, it means that the vehicle shuts off whilst you’re driving. The ignition relay gives power to the fuel pump so that the engine is kept running. If constant power isn’t given to the fuel pump, then there won’t be any fuel for the correct air-fuel mixture to be sparked therefore, the engine will shut down. An engine stalling because of limited power to the fuel pump can also be caused by a bad fuel pump relay therefore it’s important to get the problem checked out.

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3. Dead Battery

Any power the ignition relay provides to components in the vehicle is provided by the battery. This means the battery needs to have power so that it can be given to the relays. If no power is provided to the relays, they won’t be able to provide any power to the ignition, fuel system, or ignition coils for startup. Sometimes when the ignition relay fails, the ignition system can still continue to work even when the keys have been removed. Because of this, the circuit won’t be closed for the ignition to be turned off, therefore, the battery will drain. If you find that your battery is dead when it was just working, it can be an indication that the ignition relay isn’t working properly.

4. Fried Relay

If the relay is shirt circuiting easily, it might blow up due to overheating – this usually happens when the ignition is of low quality. Because all the relays are in the same location in the fuse box, they can be damaged as well because of the one ignition relay that’s low quality and overheating. If this is the case, you’ll need to replace the fuel box including the relays inside.

5. Intermittent Starting Issues

When the ignition relay is working correctly, power is sent to the starter constantly when it’s engaged. The ignition relay can get damaged with dirt overtime and this can cause it to become damaged with excessive heat. This can also cause the ignition relay to work sporadically. If you try to start your vehicle and it doesn’t start up immediately, but you turn the key once to start the ignition and it does work, chances are the relays are damaged. In this case, you’ll need to get it checked out by a mechanic.

6. Clicking Coming from Relay

If you hear a clicking sound coming from the starter when you start the ignition, this can indicate that the battery is low on amps and that the ignition relay isn’t sending a full signal. The ignition relay is an all-or-nothing device which means it either sends a full correct to the start for the vehicle to start up, or it sends nothing at all. If you hear this clicking sound, it can indicate that you have a bad ignition relay and you’ll need to get it replaced.

7. Unresponsive Fuel Pump

If your fuel pump isn’t responding when the vehicle starts, this could be a sign that the ignition relay isn’t functioning properly. When you start your car, the fuel pump will start working immediately and you might hear a slight buzzing sound that will signal this. Since the ignition relay sends some power to this component, if the ignition relay isn’t delivering the right amount of power to the fuel pump, it won’t be able to start when the car starts. The fuel pump is needed to send fuel to the combustion chamber, and this isn’t happening, the ignition relay along with the fuel pump relay could be faulty.

8. Loss of Power

If your vehicle loses power whilst you’re driving, this could indicate that the ignition relay isn’t too good. Your vehicle may stop completely, or it could lose power whilst on the road partially. This could be because the air-fuel mixture in the combustion chamber isn’t being ignited properly because the spark plugs aren’t receiving enough electricity from the ignition relay. If you notice that your vehicle loses power and you notice some other symptoms with it, then this can indicate that the ignition relay isn’t working correctly.

9. The Engine Starts for a Few Seconds

You may start your car and the engine comes on as normal and you hear all the right noises, then you may notice that the engine power goes down or turns off and you aren’t able to drive your vehicle. If the ignition relay was functioning incorrectly and not provided enough electricity to the fuel pump or ignition coil, as soon as the engine is turned on, it’ll be directly affected. Therefore, you’ll notice that the engine loses its power after being on for a few seconds. If you notice this whenever you start your vehicle, it could indicate that the ignition relay needs replacing.

10. No Noise from Fuel Pump

Along with an unresponsive fuel pump, if you turn on your vehicle and you don’t notice that there’s a noise coming from the fuel pump, this could be because of a bad ignition relay as well as a fuel pump relay. Most fuel pumps produce a humming vibrating noise that can be heard from the outside of your vehicle near the fuel tank. If the ignition relay isn’t providing the right amount of power to the fuel pump for the vehicle to start up while the ignition is on, this will stop it from working and you’ll hear silence when the ignition is on.

11. Car Not Starting

Another symptom of a faulty ignition relay is your car not starting. When your ignition relay fails, power will be cut from the fuel pump and the ignition relay and this will result in no power which means that your car can’t start. You may be trying to turn your key in the ignition or crank the ignition, but the car will be unable to start due to there not being any power to the fuel and ignition system. With this symptom, it can arise due to other causes but make sure that you’re receiving a variety of symptoms to know that the ignition relay is bad.

12. Fluctuating Ignition Power

A faulty ignition can cause your dashboard lights to blink constantly due to power coming and going from the ignition. There may be corrosion on the inside of the ignition relay which can cause the connection area inside the relay to wear down and become smaller. This will cause the ignition relay to shut off and on quickly which will affect other components in your car.

13. Bad Electronic Smell

If you notice a bad smell coming from the electronics in your car, it’s caused when the electronics create heat due to a bad connection. If the ignition relay is corroded, or damaged due to water, it can damage the connection area and cause it to heat option. If you can smell a burnt electronic smell, it’s possible that the plastic cover on the relay has melted. If you can smell this burnt smell, you should check the ignition relay and make sure that it’s good.

14. Your Starter Motor Runs Continuously

Because a signal from the relay can’t pass to the starter motor, your car won’t be able to start. Rather than an electric circuit failing to open, the ignition relay may fail to close it. This will cause the starter motor to continue running even after your engine starts – it’s meant to stop running once the engine has started but because the ignition relay can’t close the circuit, it’ll continue running.
In rare cases, the start relay may continue to run even after the key has been taken out of the ignition. If this happens, it can cause serious damage to the ignition relay and the starter motor. Although a faulty ignition relay is likely to cause this issue, it can also be caused by binding from the lock cylinder.
If you want to know if this is being caused due to binding, you can test it by rotating the lock cylinder, if rotating it causes the starter motor to stop running, then you’ll know the lock cylinder was the issue. You’ll need to treat the lock cylinder by lubricating it either using liquid graphite or dry Teflon lube. If the starter motor didn’t stop after rotating the lock cylinder, chances are your ignition relay is faulty.
If you want to know if your relay is definitely faulty, you’ll need to take it to a mechanic to get it looked at. For them to test it, they’ll simply replace the faulty relay with a fresh one and they’ll see if the problem stops. If this swap doesn’t fix the problem, the problem is probably with the ignition switch wiring.
If the ignition switch wiring is bad, the starter relay may receive an electrical ground even when the key isn’t in the ignition. To stop the starter motor relay from running even when the car isn’t turned in the ignition, replacing the faulty relay ignition wiring will fix the issue.

Causes of Bad Ignition Relay

You may notice that you have symptoms of a bad ignition relay but you have no idea how it became faulty. There are a few situations that can occur which will end up in your ignition relay failing. You may have noticed that you’ve just brought your car back from the dealership and you’re noticing symptoms of a bad ignition relay – in this case, you might be wondering how the ignition relay broke. Here are the primary causes of a bad ignition relay:


If the connection area of the ignition relay is corrodent, the correct amount of current can’t be sent to the starter motor which will result in starting issue. This could be clicking noise from the ignition relay, your car may not start, there could be intermittent starting.

Dirt and Debris

Because the ignition relay is under the hood, it’s protected from dirt and debris but over time, you’ll find that direct and debris will accumulate on the ignition relay and this will affect how it functions. When the dirt clumps up, the correct amount of current won’t be able to flow from to the starter motor and you may hear clicking sounds from the relay.

Bad Connectors

A defective or broken connector is a significant cause of a failed relay. The relay will not function properly if the required amount of current is not passing through. It will display some signs by giving a series of weak clicking sounds and unable to carry the starting circuits. Aside from the series of weak clicks, the vehicle may refuse to start.

Too Much Heat

If you notice that there’s a burning smell coming from where the ignition relay is, it could be down to melting plastic. This can happen when a high voltage is sent to the ignition relay and a high amount of heat is generated. This will cause the starter motor to close the circuit even when the ignition is off.

Overly Aged Relay

If the ignition relay has been used for hundreds of thousands of miles, then it won’t be able to function properly due to natural wear. This means that there isn’t a direct cause and it’s just that the ignition relay is too old. In this case, you’ll need to place the ignition relay as soon as possible.

Ignition Relay Replacement Cost

The cost to replace your ignition relay can be between $15 and $100 depending on the mechanic you choose. An ignition relay costs $5 to $50, and the labor costs $10 to $50. A reliable well-known mechanic will usually cost more than your local mechanic. You should look at all the mechanics in our area and determine which one is the cheapest and is the most trustworthy. The price of the ignition relay replacement is also determined by the car that you driving – the model, year, and make all affect the labor costs.

If you want to save money on the ignition relay replacement and do it yourself, down below are the steps you need to do so. The ignition relay that you need to replace can be purchased for as little as $5 – that’s for a used ignition relay. For a brand new ignition relay, it could cost upwards of $50.

If you decide to go with a mechanic since you don’t have the correct tools to perform the replacement yourself, then you should speak to some mechanics in your area. You’ll be able to get good quotes from some over the phone but if you can, go to them in person to make sure that they can actually deliver on the quote that they stated. If you’ve only been able to get one quote for the replacement, you should check with other dealerships in your area to check if you can get other competitive prices.

If you’re doing the replacement by yourself so you don’t have to spend as much on the replacement, then you should look for parts at a local scrap yard if you’re really looking to get low prices. Before you decide to go to a scrapyard, make sure that it’s specifically for car parts so that you don’t waste your time.

How Long Does An Ignition Relay Last?

You should be aware that ignition relays rarely become bad but even if they eventually do, how long would this take? Your ignition relay should last as long as your car but if it doesn’t it does tend to break around 100,000 miles. This is because the constant voltage sent to the relays can cause the connectors to become bad.

How to Fix A Bad Ignition Relay

If the ignition relay is bad, then it’s a sign that you’ve been failing to maintain your vehicle. Maintaining things like your battery and other parts of the vehicle will allow the ignition relay to function properly over a long period of time. If not, the ignition relay will go bad and you won’t be able to turn on your car’s ignition. This can cost a lot to repair so it’s best that you avoid it in the first place.

If you want to avoid ignition relay problems or other issues and save $100s of dollars that you’ll spend at the auto repair shop, you’ll need to service your vehicle often – you can use our mechanic-rated Auto Maintenance and Repair Manual to do this. It’s basically what mechanics use to go through your vehicle to check if there are any problems that need fixing. As soon as they notice the most minor problem, they’ll ask you to fork out some money even though it’s a problem you can fix yourself in minutes – the manual will teach you how to maintain your vehicle every few thousand miles and it’ll teach you how to fix minor problems that mechanics will ask you to pay for; saving you money in the long run.

A lot of our readers have the Auto Maintenance and Repair Manual printed on their garage wall and 92% of them haven’t visited the auto repair shop in the last year because they know what to do to avoid problems. All it takes is giving your vehicle a little attention every few thousand miles and you’ll never spend money at the workshop again.

Replacing a Bad Ignition Relay 

Starter relay replacement is a pretty easy and quick fix. There are several processes to follow when installing a new starter relay. It all depends on the type of relay you’re replacing.

Replacing your ignition relay is a pretty easy and simple process. Depending on the type of relay you’re trying to replace, the process is different. But for an ignition relay, it’s pretty smooth.

1. Disconnect the vehicle’s battery. You’ll need to locate the battery and disconnect the positive and negative terminals.

2. Remove the steering column. Find the plastic covers underneath the steering wheel that cover the bolts. With a screwdriver, replace the plastic cover.

3. Remove any dashboard cover(s). If your car has a dashboard cover underneath the dash near the steering column, you’ll need to remove it. In most cars, the ignition relay is behind the steering column underneath the steering wheel.

4. Find the ignition relay. Once the covers are removed, you should find the ignition relay pretty easily. You’ll notice that it’s connected to a series of wires.

5. Remove the electrical harness. After finding the ignition relay switch, you need to remove the electric connector connected to it. There may be one or two harnesses depending on your vehicle.

6. Remove the ignition relay. Remove the cover that’s on top of the relay switch. This is usually held by a bolt. Then remove the relay switch screws that attach the ignition relay to the steering column. In most vehicles, 2 to 4 screws will have to be removed to completely remove the ignition relay.

7. Reinstall the new ignition relay. Install the new ignition relay by reversing the process of when you took out the old relay. You need to attach the ignition relay to the steering column or the bracket with the screws you removed initially. Reconnect the cover that secures the harness to the ignition, then reconnect the electrical harnesses and the dashboard covers as well as the steering column cover.

8. Reconnect the battery terminals. Reconnect the positive and negative terminals to the battery.

9. Clear error codes with an OBD2 scanner. If the check engine light is on, there was a problem detected by your ECM. You can clear it using an OBD2 scanner.

10. Test the new relay. Insert your key with the door open. If you insert the key and you hear the bells ringing, the first connection is good.

Diagnosing and Testing a Bad Ignition Relay

If you want to test if the ignition relay has failed, you can test for a drop in voltage or you can test for resistance.

1. Grab a multimeter (View on Amazon) and set it to 20V DC.

2. Connect the black probe to the ignition circuit located on the fuse box.

3. Connect the red probe to the battery’s red wire.

4. Turn on the ignition.

5. If the voltage drops less the 0.2 volts, its fine. If the voltage drops more than 0.2 volts, it’s failed, and you need to replace it.

6. If you want to test it for resistance, it should give a resistance of 5 Ohms or less. If it’s more than 5 Ohms, you’ll need to get it replaced.

What To Do About A Bad Ignition Relay

If you think you have a bad ignition relay, there are a few things you can do. First off, you should identify the problem to make sure it is the ignition relay. Then, you can go about having the ignition relay replaced. If you have a bad ignition relay, here’s what to do:

Use OBD2 Scanner – You may have to use the OBD2 Scanner (view on Amazon) to reset something in your car after receiving a check engine light. If you’re receiving the check engine light and you’re noticing symptoms of a bad ignition relay, you can diagnose it using an OBD2 scanner.

To use the OBD2 scanner to detect the problem, connect the scanner to the computer port and read the trouble code for the warning light. Even if you cannot reset the light, the scanner will pinpoint the problem and help you dodge those high dealership repair prices.

Regular Inspection – Regular visual inspections of your ignition relay can reveal problems that must be addressed.

Replace the Ignition Relay – Some people are more mechanically inclined than others. Therefore, there are options for dealing with a broken ignition relay. For those with the appropriate skills, you can replace it yourself by getting a new ignition relay and replacing it. A little time and elbow grease can save you money.

Take your car to a repair shop – If you don’t have the OBD2 scanner, or you’re not so sure about fixing the ignition relay yourself, take your car to an automotive repair shop as soon as possible. A car that’s not starting properly means that the vehicle is in need of some type of maintenance. If your vehicle has not been serviced regularly, these types of problems can escalate into major problems which are more expensive to fix.

Prevention of Bad Ignition Relay

Ignition relays will go bad from time to time. Even so, there are only a few things that you can do to avoid ending up with a bad ignition relay. If you already have a vehicle that is having problems with the ignition relay, it’s best to seek professional help or replace it. However, if you have not yet experienced any of the symptoms mentioned in this article, you can begin with preventive maintenance following these steps:

1. Engage in Preventive Maintenance

Have your vehicle inspected by a professional so that you have a clear picture of your ignition relay’s condition? If you perform the inspection yourself, make sure to check all of the components in the ignition.

2. Keep It Clean

The ignition system is comprised of many small parts. Make sure those parts in your ignition system are clean and lubricated. The ignition relay connectors can become corroded which is guaranteed to cause malfunction. Take your vehicle to an automotive shop for scheduled maintenance and mention that you would like to have the ignition relay examined.

3. Don’t Drive

If you have discovered that your ignition relay is been damaged, don’t drive. Arrange for other modes of transportation until the ignition relay is repaired and you can drive safely.

Job Guthiri is a freelance writer with 3 years of experience writing for Motorsrun and other established automobile outlets. His focus and key interests are Tacomas and maintenance. Read our Editorial Guidlines and Fact Checking process.