Fiat Check Engine Light: Reset, Flashing, Troubleshooting Guide

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 a transmission problem.

The light itself does not provide much information other than to warn you to get the car diagnosed. Knowing why your Fiat check engine light is on is impossible without reading the codes. You will learn how to read codes in the next section.

Symptoms

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?

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 and 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.

Many more possible problems and hundreds of Diagnostic Trouble Codes (DTC) can trigger the CEL on your Fiat. It is difficult to know the problem in your particular case without diagnosing the vehicle.

How to Reset Fiat Check Engine Light

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.
2. Plug 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, requiring you to look carefully under it.
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?

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 returns 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

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.

If your Fiat check engine light is NOT flashing, it is usually safe to drive. If you drive your Fiat when the CEL stays on, you should monitor dashboard warning lights and the engine temperature. Do not drive if the engine shakes 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.