A Fiat check engine light is a warning indicator that alerts drivers of a potential issue with their vehicle’s engine or emissions control system. When the check engine light illuminates in a Fiat vehicle, it’s important to address the issue promptly to maintain the performance and efficiency of the engine. This guide provides information on what to do if the check engine light is on, including resetting the light, troubleshooting common causes, and understanding the flashing pattern.

In newer Fiat models, such as the late-model Fiat 500, you will note the “HAVE YOUR ENGINE CHECKED” message on the dashboard. The problem could be something as simple as a loose gas cap (fault code P0456) or an indication of another problem, such as a turbo boost issue, engine malfunction or misfire, or even a transmission problem. The light itself does not provide much information other than warn you to get the car diagnosed. Without reading the codes, it is impossible to know why your Fiat check engine light is on. You will learn how to read codes in the next section.


fiat check engine light

A list of symptoms you may notice when your Fiat check engine light comes on.

  • Poor throttle response,
  • Engine jerking when changing gears,
  • Engine overheating
  • “high coolant temp, turn the engine off” warning,
  • Engine stalls at idle, or the car is difficult to start.

The symptoms of Fiat check engine light vary. Sometimes you may not notice any performance issues at all. If you don’t notice any performance issues, you can continue to drive your Fiat but get it diagnosed as soon as possible.

Why is my Fiat check engine light (CEL) on?

Troubleshooting Alfa Romeo Check Engine Light

The most common problems triggering Fiat check engine light are worn spark plugs or a loose gas cap.  Other issues can trigger the check engine light on a Fiat, such as:

  • Poor fuel: Low-quality gasoline can trigger the CEL on Fiat vehicles
  • Turbo problem: Under boost pressure
  • Thermostat: Engine overheats or takes too long to reach operating temperature
  • Oxygen sensor: Increases emissions a decreases fuel economy.
  • Mass airflow sensor: Often results in multiple codes and poor throttle response
  • Spark plugs: If one fails, it will cause an engine misfire and engine shaking
  • EVAP: The EVAP emissions canister can fail, triggering CEL and codes such as P0499.
  • PCM: Failure to change spark plugs and wire harness does not fix the CEL. PCM replacement may be required.

Note that many more possible problems and hundreds of Diagnostic Trouble Codes (DTC) can trigger the CEL on your Fiat. Without diagnosing the vehicle, it is difficult to know what the problem is in your particular case.

How to Reset Fiat Check Engine Light

fiat youcanic scanner

The following instructions work on Fiat vehicles manufactured from 1996 to the present. An OBD-II scanner is required to read the codes. The YOUCANIC Full System Scanner can read and clear fault codes on every control module of your Fiat vehicle.

  1. Turn on Ignition. All your dashboard lights should be on. Do not start the engine.turn fiat ignition on
  2. Plugin your scanner into the OBD II port under the dashboard. There is only one port like this. Sometimes it has a small cover, so you may not notice it easily. It may be hidden under the dashboard, which will require you to look carefully under the dashboard.fiat port to diagnose check engine light
  3. Allow the scanner to communicate with your Fiat and detect the correct protocol.
  4. Press read codes on your OBDII scanner or phone app to retrieve the codes.
  5. Fix the problem that triggered the codes you retrieved in step 4; return to the main menu and select Clear Fault Codes.

These instructions will allow you to check engine codes on Fiat models such as Fiat 500, 500x, Abarth, Panda, Fremont, Viaggio, Ottimo, Ducato, Dublo, Tipo, Toro, Mobi, Argo, Punto, Panda, Croma, Sedici, Bravo, etc.

Can a loose gas cap trigger the check engine light?

fiat loose gas cap triggered check engine light

Yes. If you scan your Fiat and the code you get for EVAP leak, ensure you tighten the gas cap until you hear two clicks. You can also use an OBD-II scanner and clear the code once you tighten the gas cap. If the CEL comes back, replace the gas cap.

If the CEL comes back with a code for a small EVAP system leak, have a mechanic, or your Fiat dealer would have to perform a smoke test to find the leak.

It is strongly recommended to write down the code and research the problem. Many owners get a code and start replacing parts based on the code alone. Don’t start replacing parts without researching the code first. There is more than one problem that can trigger one code.

Fiat Check Engine Light Flashing On and Off

fiat check engine light flashing

If your Fiat check engine light is flashing, the onboard diagnostics system (OBD) has detected an engine misfire. In other words, one or more cylinders are not working properly. It is not recommended to drive your Fiat if the check engine light is flashing. Driving your Fiat with CEL flashing can cause more damage to the engine and catalytic converter.

As long as your Fiat check engine light is NOT flashing, it is usually safe to drive. If you decide to drive your Fiat when the CEL stays on, you should monitor dashboard warning lights and the engine temperature. Do not drive if the engine is shaking or hesitates when pressing the gas.

We hope you find this guide, “Fiat Check Engine Light Stays On,” helpful. Check these troubleshooting and repair guides for more help on your Fiat.

Leave a Reply

Your email address will not be published. Required fields are marked *