Nowadays, there’s so much history about cars that we take for granted. For instance, the check engine light. Maybe you’ve never given it much thought, but aren’t you a little curious about how it came to be? Today, we’re covering the complete history of this handy invention, so buckle up and enjoy the ride.

History of how the check engine light work?

A check engine light is sometimes called a malfunction indicator lamp, or MIL for short. It’s a computerized warning light that indicates an engine malfunction. Typically found on the instrument panel, it’s the red or orange light that lets you know if there’s a problem. It either looks like a picture of an engine, or will sometimes read as a phrase such as “SERVICE ENGINE SOON”. If the light is blinking, it indicates an imminent problem, and you need to get help right away. When the MIL lights up, the engine control unit saves a fault code that’s read by a scan tool to diagnose the issue. An activated MIL indicates a variety of vehicle issues with a wide range of severity.

When was the check engine light standardized in History?

The check engine light as we know it didn’t appear in vehicles until 1996. It came with the second generation of on-board vehicle diagnostics, known as OBD2. Starting in 1996, OBD2 became a requirement for all cars sold in the United States as part of a federal mandate to lower vehicle emissions. O​BD2 technology resulted in the development of a standardized system of fault codes. Because of this system, our experienced technicians at Blaine Autocare can use scan tool technology on any vehicle built in 1996 or later. This allows us to easily see why your check engine light is activated.

The History and How has the check engine light evolved over time?

Back in the early 1980s, check engine lights were only in vehicles with computerized engine controls. This was before the regulations that came with OBD2 technology. These early diagnostic systems were quite basic in comparison to what we have today. Instead of being standardized, they were only capable of monitoring manufacturer-specific automobile issues. As a result, it was much harder for auto technicians to figure out what activated the check engine light. Back then, scan tool technology wouldn’t work with two different vehicle models, even if both vehicles had the same issue.


The most rudimentary form of the check engine light was called an idiot light (no joke), or warning light. Through history, these binary lights only activated when a major issue or breakdown was about to occur. They provided no advance warning or detection of a vehicle fault. The first manufacturer to use them was the Hudson Motor Car Company. They started putting these warning lights in their cars sometime during the mid-1930s. When check engine lights became popular through history in the 1980s, idiot lights were discontinued to avoid confusion.


Luckily, we’ve come a long way since then in history. These days, experienced technicians can diagnose any vehicle issue in no time. Since today’s check engine lights are activated for a variety of reasons both large and small, they often detect vehicle issues early on. This saves you time and money on repairs in the long run.

Well, there you have it. Everything you didn’t realize you wanted to know about your car’s check engine light and the history of it. The next time your car’s check engine light is triggered, just be thankful it’s not an idiot light. Think of it as your car’s way of letting you know it needs a little TLC, and give us a call.


8 Reasons Your Car’s Check Engine Light is On and What You Need to Do About It

As you’re driving, you look down at your dashboard and notice that the check engine light (CEL) appeared. You hate to see it. The truth is, the CEL can be triggered by any number of engine problems. Today we’ll discuss 8 reasons why your CEL is on and what to do about it.

1. Loose or missing fuel cap

One of the most common causes for the CEL is a loose or cracked fuel cap. The fuel cap keeps vapors from leaking out of your vehicle. If this seal is faulty, your CEL will turn on. Luckily, this is a relatively minor repair. Putting this off will result in poor fuel economy and increased emissions.

2. Oxygen sensor

Another reason you may be seeing the CEL is the oxygen sensor. This sensor determines the amount of oxygen present in the exhaust. It allows your engine to perform at maximum efficiency by adjusting the amount of fuel. A faulty oxygen sensor will cause your car to use up more gas than it needs. Delaying this repair could damage your catalytic converter, costing you thousands of dollars.

3. Spark plugs and spark plug wires

Old or faulty spark plugs and spark plug wires can also activate the CEL. Your spark plugs and wires are what ignite the air and fuel mixture in your car’s engine. This produces power and makes your engine turn. If these aren’t working correctly, it can weaken engine performance and lead to poor fuel economy. Luckily, spark plugs are inexpensive and easy to replace. Putting this off can clog the catalytic converter or damage the oxygen sensors.

4. CEL & Catalytic converter

Your CEL may turn on because of a clogged catalytic converter. Since this part doesn’t need routine maintenance, it usually indicates another underlying problem. Unfortunately, this isn’t a cheap fix. Routine maintenance and repairs can prevent a clogged catalytic converter, saving you time and money in the long run.

5. Battery

A faulty or undercharged car battery will lead to low voltage, which may cause your CEL to turn on. Modern batteries are maintenance-free and last around 5 to 7 years. While this isn’t a common reason for the CEL, it’s still possible.

6. MAF failure

The mass air flow (MAF) sensor can also trigger your car’s CEL. The MAF sensor measures the exact amount of air that enters the engine. This tells your car how much fuel it needs for it to run smoothly and efficiently. One of the most common reasons for an MAF problem is not changing your air filters. If it’s not resolved in a timely manner, MAF failure can damage lots of other engine parts.

7. EGR valve

The exhaust gas re-circulation (EGR) system lowers the combustion temperature. It does this by rerouting a small amount of exhaust gases back into the engine intake. It controls the flow of gases from the exhaust manifold to the intake manifold. If the EGR flow is more or less than expected, it’ll activate your car’s CEL. EGR valves don’t need regular maintenance but they can get clogged by carbon build-up.

8. Vacuum leak

Your car’s vacuum is connected to several different parts, including the cruise control, heating and A/C vents, exhaust, and brake booster. The vacuum is a set of rubber hose lines. A vacuum leak happens when the rubber stretches out or cracks. When this happens, it triggers the CEL.

As you can see, your car’s CEL could indicate any number of engine issues, some of which have other underlying causes. Although it’s probably not something you want to deal with, routine maintenance will save you from bigger headaches down the road. Our skilled technicians at Blaine Auto Care are always here to help. Give us a call at (763) 755-7255, or stop on by today.



What Should You Do If Your Check Engine Light Comes On?

So, your check engine light is on. Now what? The check engine light can indicate any number of problems, from simple to serious. Resist the temptation to ignore this warning. Doing so could end up costing you more down the road. Keep reading to find out what steps you need to take if your car’s check engine light is on.

Should I continue driving?

If the check engine light is triggered, it’ll appear in one of two ways. When you have a major problem that needs immediate attention, you’ll see a blinking check engine light. If this is the case, pull over immediately. A check engine light that’s not blinking but is illuminated indicates a problem that usually isn’t an emergency. However, you still need to address it as soon as you can.

Regardless of how your check engine light is displaying, you should always inspect your vehicle for signs of a serious problem. For example, abnormal noises, engine smoke, and loss of power are all signs that you may have a serious issue on your hands. If that’s the case, avoid driving your car if possible. This can cause further damage to your vehicle. Instead, get it towed to a service provider for a comprehensive inspection.

Troubleshooting the check engine light

If you don’t notice anything urgent and if your check engine light isn’t blinking, there’s a few steps you can take to troubleshoot the issue. The first thing you want to check is your gas cap. Believe it or not, a loose gas cap can trigger your car’s check engine light. If you tighten the gas cap and your check engine light turns off, then you may be in the clear.

Another place to check is the oil dipstick. Make sure this is properly seated. Also make sure that the oil fill cap, which is on top of the engine valve cover, is secured tight. These can also activate the check engine light. Another option you have for troubleshooting your car’s check engine light is to use an OBD2 scanner. This tool can read the diagnostic trouble code (DTC) that set off your check engine light. To retrieve this code, you need to connect your OBD2 scanner to the data link connector. This is usually found underneath the dashboard on the driver’s side.

There are lots of good OBD2 scanners that cost under $100. While it won’t give you specific information on your engine malfunction, the DTC can give you an idea of where the problem might be coming from. This can help you decide whether to make the repair yourself, or to seek help from a professional. When you see your check engine light, don’t panic. Take a deep breath and assess the situation. Make an informed plan to resolve the problem systematically. If it’s an urgent matter, seek help right away. If the check engine light isn’t blinking, make a logical plan for troubleshooting.

Our experienced technicians at Blaine Auto Care & Transmission can diagnose and resolve any vehicle issue to get you back on the road in no time. Give us a call at (763) 755-7255, or schedule your appointment online​ today. We’re always here to help.