Why Is My Check Engine Light On? | Jay Malone Motors Service

What does the check engine light actually mean?

The check engine light is your vehicle’s onboard diagnostics system telling you it has detected a problem somewhere in the engine, emissions, or related systems — and it has stored a trouble code that pinpoints where to look.

Every modern Jeep, Ram, Dodge, and Chrysler runs a continuous self-check of dozens of systems. When a reading falls outside the expected range, the computer logs a diagnostic trouble code (DTC) and turns on the check engine light to get your attention. The light itself doesn’t tell you what’s wrong — it tells you that something is worth looking at. Two vehicles can show the same light for completely different reasons: one might have a loose gas cap, another a failing oxygen sensor. That’s why guessing rarely works, and why pulling the code is the first real step toward a fix.

Is it safe to drive with the check engine light on?

It depends on whether the light is steady or flashing. A steady light usually means you can drive cautiously to your destination and schedule service soon. A flashing light is a warning to stop driving as soon as it’s safe.

A steady check engine light generally points to a less severe issue. If your vehicle is driving normally with no change in performance, it’s typically safe to keep driving for a short time — but don’t ignore it. The underlying issue can get worse and more expensive the longer it goes unaddressed.

A flashing check engine light is different. It almost always signals an active engine misfire, which dumps unburned fuel into the exhaust and can quickly overheat and damage the catalytic converter — one of the more expensive repairs you can run into. If your light is flashing, especially alongside rough running, shaking, or a loss of power, pull over when it’s safe, shut the engine off, and arrange a tow rather than driving it any farther.

Important: If the check engine light is flashing — or any light is paired with smoke, a burning smell, overheating, or a sudden loss of power — treat it as urgent. Stop in a safe spot, turn the engine off, and call us at (320) 587-4748 before driving any farther.

What are the most common reasons the check engine light comes on?

The causes range from a loose gas cap to a failing catalytic converter, but a handful of issues account for most check engine lights we see.

Some of the most common triggers include:

• Loose or damaged gas cap. The single most common cause, and the easiest to rule out. A cap that isn’t tightened, or one that’s cracked, breaks the seal in the fuel system and trips the light. Tighten it (or replace it) and the light may clear on its own after a few drives.
• Oxygen (O2) sensor. This sensor measures oxygen in the exhaust. A worn one throws off the fuel mixture, hurting fuel economy and emissions.
• Catalytic converter. Often a downstream consequence of an ignored misfire. A failing converter restricts exhaust flow and can trigger a flashing light.
• Spark plugs or ignition coils. Worn plugs or a failing coil cause misfires — rough idle, hesitation, and sometimes a flashing light.
• Mass airflow sensor. This measures the air entering the engine. Faulty readings can cause rough idling and stalling, and it shows up more often on vehicles driven on dusty gravel roads — common around McLeod County.

Because so many different problems can light up the same icon, the diagnostic code is what separates a two-minute gas cap fix from a repair that needs real attention.

Can Minnesota cold make the check engine light come on?

Cold weather doesn’t usually create new problems by itself, but a Minnesota winter can expose and worsen issues that were already developing.

Deep cold is hard on the components that keep your engine running cleanly. Weak ignition parts, aging spark plugs, and small vacuum leaks all behave worse when the temperature drops, which means a borderline component that held on through summer may finally trip the light on a sub-zero Hutchinson morning. Cold also thickens fluids and strains the battery, and a struggling start can occasionally set related codes. If your check engine light appears for the first time during a cold snap, it’s worth getting it read before winter driving puts more stress on it — especially if you’re regularly on US-7 or MN-15 in the worst of it.

Should I reset the check engine light myself?

Resetting the light without fixing the underlying cause only hides the problem — the code will return, and you may make things worse in the meantime.

It’s tempting to clear the light and move on, but the light is a symptom, not the disease. Clearing the code before the issue is repaired can mask a problem that’s actively causing damage — and it erases the very information a technician needs to diagnose it. The right order is to read the code, address the cause, then verify the repair cleared the system. Worth knowing: modern vehicles store the trouble code even if the light later turns off on its own, so a technician can still retrieve it during service.

Why bring it to Jay Malone CDJR instead of clearing it at a parts store?

A parts-store scanner can read a generic code, but our factory-trained technicians use the diagnostics built for your specific vehicle to find the real cause — and we back the repair with genuine Mopar parts.

A free code read at a parts store can be a useful starting point, but a generic code often points to a symptom, not the root cause — replacing the wrong part is a common and costly result. Our service team uses factory-level diagnostics and the kind of model-specific knowledge that comes from working on Jeep, Ram, Dodge, and Chrysler vehicles every day. We’ll tell you what’s actually wrong, what it’ll take to fix it, and what can wait.

And you don’t have to drive one of our brands to get that help. Our certified technicians service all makes and models, any year, whether or not you bought the vehicle from us. If you’re in Hutchinson, Litchfield, Glencoe, Dassel, Cokato, Brownton, or anywhere across McLeod County and central Minnesota, you’re welcome in our service lane.

Frequently Asked Questions

Can I keep driving if my check engine light is flashing?

It’s best not to. A flashing light usually means an active engine misfire, which can quickly damage the catalytic converter. Pull over when it’s safe, turn off the engine, and arrange to have the vehicle towed in rather than driving any farther.

Will my check engine light turn off on its own?

Sometimes. If the cause was something minor like a loose gas cap, tightening it can let the light clear after a few drives. But the trouble code stays stored in the vehicle’s computer even after the light turns off, so it’s still worth having it read to confirm the problem is actually resolved.

Is a free parts-store code read good enough?

It’s a fine starting point, but a generic scanner often reports a symptom rather than the root cause — which can lead to replacing the wrong part. Our factory-trained technicians use diagnostics built for your specific vehicle to pinpoint the actual problem before any work begins.

Do I have to own a Jeep, Ram, or Dodge to get service here?

No. Our certified technicians at Jay Malone CDJR service all makes and models, any year, whether or not you purchased the vehicle from us. If your check engine light is on, you’re welcome to bring it in no matter what you drive.

Should I be worried if the light comes on in cold weather?

Cold weather rarely causes the light on its own, but it can push a marginal component — like an aging spark plug or a small vacuum leak — over the edge. If your light first appears during a Minnesota cold snap, it’s a good idea to have it read before winter driving adds more stress.

We’ll figure out what your vehicle is telling you

A check engine light is one of the most misunderstood warnings on the dash — it can mean a thirty-second gas cap fix or something that needs real attention, and there’s no way to know for sure until the code is read. That uncertainty is exactly why we’re here. Bring it to our service team in Hutchinson and we’ll give you a straight answer about what’s going on and what it’ll take to make it right.

We’ve been a family-owned part of this community since 2005, and we treat the people who walk into our service lane like neighbors, not transactions. Whether you drive a Jeep, a Ram, a Dodge, or something else entirely, we’d be glad to take a look. That’s the “Your Dealer for Life” promise — and it doesn’t expire when the warranty does.

Last reviewed June 2026 by Brady Forst, Jay Malone CDJR.