Check Engine Light Not Flashing And Not Working (Possible Causes & Fixes)
So your car check engine light is not flashing and not working? You’re worried about what could have caused it to malfunction and what you can do to fix it? If that’s you, we have put together this guide to help you out.
Check engine light not flashing and not working means the bulb or a fuse is burned out. A defective ECM (electronic control module) could also cause the check engine light not to come on.
The following guide discusses more details about why your car check engine light is not flashing and not working, how much you may need to spend to fix the light, and other helpful info you need to know.
Why your check engine light is not flashing and not working:
Your check engine light not blinking and not working is only a good thing when your car is running in good condition and not throwing any codes.
However, if the light doesn’t come on when you turn on your car or when there’s an issue with your car, then you should be worried.
The most common reasons why the CEL wouldn’t work include the light burning out. This is especially true if the dashboard displayed the light before and then it fails to come on again.
If the dashboard light is working, then your car ECM could be faulty—making the light fail.
You can try removing a sensor harness to see if the CEL comes on. If it does, it means the system isn’t faulty. If it doesn’t, consider checking the car computer for trouble codes for the sensor harness you have unplugged.
If it throws a code and the MIL indicates reads “ON,” then your check engine light is burned out.
You can have a professional mechanic carry out a check engine inspection. The mechanic usually attempts to access the ECU using a scanner to see if it connects and is in good condition.
In the worst-case scenario where the computer is damaged, only a dealer can replace your car ECM or an authorized mechanic for your car, which can get quite pricey!
Other possible causes for the check engine not coming on include a damaged fuse, an issue with the dashboard itself, or a damaged electrical relay.
The light may also have been disconnected intentionally. This is common when you buy a used car. The car owners or unscrupulous dealers are trying to hide engine malfunctions and make the car appear in good condition to potential sellers. They usually do this to avoid expensive repairs or to pass car inspections.
That’s why it is always recommended to check the CEL light when you turn on the ignition. If the light doesn’t come on, that’s a massive red flag and you should away from that deal!
Check the video below on how to inspect your dash for a missing check engine light.
Why does check engine light not come on when key is in on position?
If you turn on your car and check engine light won’t come on, then you should also be worried as the car won’t pass the smog test. Even if your car runs fine and passes the emissions part of the test, it still won’t pass the smog test.
Under normal circumstances, the check engine light ought to come on briefly when you put the key in position and go off after the engine starts. If the light doesn’t come on, then a fuse or the CEL bulb could be burned out in the cluster.
As we mentioned above, a light that has been intentionally disconnected by the previous car owner or a car dealer can also cause the CEL not to illuminate when you turn on the ignition.
If this is your case, try reading out the error codes using a scanning tool to give you a better idea of what issue is being hidden and have it fixed by a reputable mechanic.
Can a check engine light be faulty?
Yes, a check engine light can be faulty. For starters, the check engine uses a bulb just like other lights. This means after it has been coming on for long enough, it will eventually go out (get burned out).
If you believe that your CEL light has blown out, you may need to have it replaced with a new one and it should continue working fine.
To replace the CEL, you’ll need to remove trim panels from your dashboard. This will give you easy access to the circuit board which controls all dashboard lights.
The bulbs used may vary from one car model to another. In some cases, the bulbs are attached to the circuit board via a twist socket. Others are directly soldered to the circuit board.
Unless you have good electronics skills and you can easily take the dashboard apart on your own, we recommend taking your car to a repair shop to have a professional do the bulb replacement for you.
Is it expensive to fix a check engine light?
Fixing a burned-out bulb for the check engine light isn’t expensive. You’ll just need to cover the bulb cost which is roughly $10 plus repairs cost which can be anything up to $200.
Bulb replacement can be done by a decent mechanic and won’t cost you a lot of money.
Even better, you can do the bulb replacement on your own (as explained in the previous section) and save yourself the repair costs.
However, if the issue causing the CEL to fail is a faulty ECM causing the check engine light not to work, then it will become an expensive fix. This fix can only be done by the dealer or an authorized mechanic for your car brand.
Before you do anything that might cost you a lot of money, try replacing the bulb for the CEL. In simpler words, try making the easy fixes first and see if they help solve the problem.
How do you know if the check engine light has been tampered with on your car?
The easiest way to tell whether your check engine light has been interfered with is by turning the key into the ON position. if the light doesn’t come on, it means the light has been interfered with.
In an ideal situation, the light is supposed to come on for a few seconds whenever you start your car. As you already know PCM controls the CEL and it must conduct a bulb check to inform you that the light is functioning properly.
If the light doesn’t come on with the key in position, then it’s most likely the bulb has burned out or been tampered with.
You can go ahead and check whether the bulb is available using the method we explained earlier. Or if you’re not confident in your electronic skills, you can get a decent mechanic to inspect the CEL for you.
Most cases of CEL tampering happen when you’re buying a used car from another individual or from an unscrupulous dealer. They tend to remove the CEL as a way of hiding those expensive repairs and making the car appear to be in good condition.
Some dealers and individuals simply put black tape between the panel and the bulb so you can’t see the CEL on your dash. Others simply remove the bulb so the light never comes on.
Some dealers are also clever enough to rewire the light such that it illuminates briefly when you turn your car on but it doesn’t illuminate when a fault code is detected.
To avoid such instances, it’s always advisable to have an independent mechanic inspect the car, including its wiring, before you close a deal.
What does it mean if the check engine light off but code is still there?
If the check engine light is off but the code is still there, this is not normal since the light should show up to alert you of a problem with your vehicle. So, what could cause the light not to come on while the code for the problem is still there?
One possible explanation is that the problem that threw a code hasn’t happened enough times to make the light come on. This means the problem isn’t critical and the trouble code is pending and you have nothing to worry about.
But if you want to stay clear-headed, you can use an OBD2 scanner to help you identify the problem.
Another reason why you see codes but no CEL is that it could be a non-emissions related issue. These problems usually don’t offset the check engine light.
The code could also have been stored in long-term memory. Whenever your car system throws a code, it stays in the memory even after CEL goes off and it clears within two weeks if the problem doesn’t reoccur.
Or it could be that the powertrain control module (PCM) has wiring issues or simply poor electrical connection which means the CEL can’t illuminate even when there’s a trouble code available.
In any of these cases, you should use an OBD II scanner to help you pull the trouble codes and identify what the problem is. Alternatively, you can take the car to a mechanic to diagnose and fix the problem.
If your check engine light is on but not flashing or not working, you might find our articles on the causes of the check engine light helpful. One of the most common reasons for the check engine light to come on is a loose gas cap. Our article on can a loose gas cap cause the check engine light to come on? explains why a loose gas cap can trigger the light, how to check for it, and how to fix it. On the other hand, if your check engine light has disappeared, it might be a good sign, but it’s important to understand why it happened. Our article on why did the check engine light disappear? explores some of the reasons why the light might turn off on its own and what you can do to prevent it from happening again. With our expert advice, you’ll be able to diagnose and fix your check engine light issues like a pro!Frequently Asked Questions:
Yes, the check engine light can stop working if its fuse or bulb gets burned out. If the bulb has been intentionally removed, then it also won’t be illuminating even where are error codes. We have explained how to replace a blown bulb to bring your CEL back to life. We have also explained how to check if the bulb has been removed or tampered with before buying a used car.
You can easily tell whether your CEL is working by checking if it turns on when you put the key in the ON position. If it doesn’t come on briefly, then the light isn’t working. You should go ahead and check whether the bulb is burned out or has been removed and then have it fixed so that the CEL can continue working.
If the check engine light is always off and the bulb isn’t blown, it means the light may have been tampered with by a previous owner (if you have a used car) to avoid fixing an expensive issue and sell it to the buyer so they can pass the problem over to the new owner. The bulb could also have been black taped or the dashboard CEL insignia painted so you can’t see it illuminating.
Final Verdict
When your check engine light won’t flash or come on, not even when you turn on your vehicle, it means something is off and you should be worried. The most common reasons why the check engine light fails to come on include a burned-out CEL bulb, fuse, and a dead vehicle computer. A CEL that has been tampered with will also fail to come when you start your car.
Luckily, check engine repair is a cheap fix and can be done by a decent mechanic. The bulb itself costs just $10 to replace. The total repair costs can add up to $200, which is on the lower end compared to more expensive car fixes.
