Why is my check engine light on but no codes?

Generally if the light is coming on and no codes are stored the processor that triggers the light is faulty or the circuit is shorted to power. disconnect that circuit from the ECU if the light goes off probably an issue with the ECU, if the light stays on look for a short to power on that circuit.

Why is my car not reading codes?

Blown Fuse If you’ve plugged into your car’s diagnostic port and aren’t reading anything, you might think that your OBD-II brain has been fried, but don’t declare it dead yet. The most common reason for getting no OBD code is simply a blown fuse. Remember that your car or truck might have more than one fuse box.

Can AutoZone read codes without check engine light?

Most AutoZone locations will generally read the OBD2 codes stored in your car’s engine computer. The stand-alone scan tools to do it start at about $20. However, this is only part of what’s necessary to actually fix your car.

Can a sensor cause check engine light?

Faulty O2 Sensors A failing sensor can cause the check engine light to be triggered, though you can continue to drive relatively fine with it. Over time it will cause more fuel consumption and damage to the catalytic converter, however, and so re recommend replacing it as soon as possible.

Is it okay to drive with check engine light on?

The rule of thumb is that if the check engine light is flashing, you can’t keep driving the car. It’s an emergency. Often it indicates an engine misfire. If you keep driving, you will likely cause irreversible damage, mostly to the (expensive) catalytic converter.

Can a check engine light mean nothing?

Normally, the appearance of a check engine light indicates a problem somewhere in your vehicle, but nothing seems amiss. Your car is still running at its best and there seems to be absolutely nothing wrong. It doesn’t have to take a mechanical issue in order for this light to appear.

Why is my check engine light on and car shaking?

The check engine light will come on when any of the following issues are detected by your vehicle’s computer. Shaking or vibration may be caused by things such as faulty spark plugs, poor fuel pressure or misfires. The other issue that may cause this type of shaking or vibration is a broken engine mount.

What is the most common problem when the check engine light comes on?

A loose fuel cap is one of the most common reasons why the check engine light turns on. The cap is a crucial part of a car’s fuel delivery system. It notably prevents gasoline fumes from leaving the fuel tank, and it helps keep the whole system under the correct pressure.

What does it mean when your check engine light is pending?

If a problem occurs but does not meet the software’s threshold for the number of times the problem must occur before lighting the check engine light, the trouble code may be stored as a PENDING CODE. In that case, you could scan the computer and find a code, even though the light wasn’t on.

Why does my check engine light come on with no code?

One main reason that a check engine light comes on with no code being stored is that there is a software error. This is often the result of something being wrong with the OBD reader that the driver, parts store, or mechanic shop is using. Most frequently, the software errors stem from a low-level OBD reader being used.

How do Check Engine lights work on a car?

Many car makers design their computers to alert the driver of a problem by turning on the check engine light and storing a trouble code in the computer’s memory.

Should you fix a check engine light that flashes or solid?

The bottom line is you should always get your vehicle diagnosed and repaired regardless of whether the check engine light is solid or flashing. A flashing light conveys an urgent issue that needs to be taken care of right away. To protect your vehicle—and avoid costly repairs— seek a mechanic’s help as soon as possible.