What Does the Catalytic Converter Warning Light Mean?

Catalytic converters are one of the most important additions to the modern automobile. Without them, the quality of air around areas with lots of traffic would be significantly worse. Using chemical reactions, the rare metals inside the converter break down the harmful gases coming out of the exhaust into their basic components, which aren’t harmful.

The catalytic converter works along with the oxygen sensors built into the exhaust system to monitor the fumes coming out of the engine and help the car stay as efficient as possible. A malfunctioning catalytic converter will throw off the oxygen sensor readings and your engine will not run as efficiently.

What the catalytic converter warning light means

This light is made to warn the driver that the catalytic converter is either overheating or not operating as intended. The inside of the catalytic converter consists of a honeycomb design that increases the surface area in contact with the air. Over time, the metal can start to deteriorate and plug up the holes leading to overheating issues caused by restricted airflow. The oxygen sensors can also malfunction leading the computer to think that the converter isn’t working properly.

Always have the oxygen sensors tested before replacing the catalytic converter. On newer cars, most manufacturers have gotten rid of the separate warning light for the converter and have tied in any issues with the converter into the check engine light. Similar to the functioning of the check engine light, when this light comes on, you may or may not notice a difference while you are driving. Either way though, you should never ignore this warning light. The car’s computer will store a code to help you identify the cause of the problem. A certified technician will be able to hook up a scan tool to the car and read the code.

Is it safe to drive with the catalytic converter warning light on?

If you don’t experience any significant difference while driving, then you should be okay for the time being. You still need to get the light checked out as small issues pretty much always turn into bigger issues, if neglected. In the event that significant damage has or will occur, some vehicles may not even let you start the engine. Like many other components on your car, you can usually save the catalytic converter by noticing the warning signs and rectifying them quickly.

If your catalytic converter warning light is on, get one of our certified technicians to help you diagnose any issues.


Next Step

Schedule Warning Light is on Inspection

The most popular service booked by readers of this article is Warning Light is on Inspection. Once the problem has been diagnosed, you will be provided with an upfront quote for the recommended fix and receive $20.00 off as a credit towards the repair. YourMechanic’s technicians bring the dealership to you by performing this job at your home or office 7-days a week between 7AM-9PM. We currently cover over 2,000 cities and have 100k+ 5-star reviews... LEARN MORE

SEE PRICING & SCHEDULING

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Recent Warning Light is on Inspection reviews

Excellent Rating

(238)

Rating Summary
224
5
4
0
5
224
5
4
0
5

Jason

15 years of experience
344 reviews
Jason
15 years of experience
Nissan Armada V8-5.6L - Warning Light is on - Mineola, New York
Excelente. Jason es todo un profesional con mucho conocimiento en la mecanica, buena persona educado y amigable. Gracias Jason.
Ford Taurus - Warning Light is on - Jamaica, New York
Very Professional definitely takes his time to find out exactly what’s the problem with the car! I was up and running in no time ! Will definitely recommend Him to anyone having issues with cars!!!

Nicholas

11 years of experience
585 reviews
Nicholas
11 years of experience
Chrysler 300 V6-2.7L - Warning Light is on - Durham, North Carolina
Excellent diagnostician. Knowledgeable and caring. Created a desire for him specifically, to do the job. Hope we get him every time!
Honda Accord - Warning Light is on - Garner, North Carolina
I was very happy with Nicholas and his knowledge and expertise about diagnosing the issues with my car. He is honest, reliable and professional. He is now my Mechanic that I will call on for all my car's needs.I will also recommend him to my friends whom have been taken advantage of by other car shops as I have been, and are looking for someone honest , that will not take advantage of them Thank you so much Nicholas for resolving my issue with my car. I feel relieved and happy with the outcome

Tony

40 years of experience
12 reviews
Tony
40 years of experience
Cadillac Escalade EXT V8-6.2L - Warning Light is on - Stockton, California
Good,mechanic helpful ,smooth move but quick, friendly patience and deep experience as a mechanic,as a customer I recommend Tony Crockett if you need a mechanic.

Brent

8 years of experience
56 reviews
Brent
8 years of experience
Jeep Grand Cherokee V6-3.7L - Warning Light is on - Lithonia, Georgia
On time for appointment. Knowledgeable, he explained what he was doing & then explained his findings to me. Later he sent a text with the diagnostic findings,

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

Related articles

What Does the Fuel Cap Warning Light Mean?
The fuel cap light tells you when a leak has been detected in your car, most likely from a loose gas cap.
What Does the Headlight Range Control Warning Light Mean?
The headlight range control warning light alerts you when the control system is defective and needs service or repair.
What Does the Lane Departure Warning Light Mean?
The lane departure light means the vehicle is detected to be moving out of its current lane without signaling. It may assist to keep you in your lane.

Related questions

Airbag warning light is on, are the airbags broken?
This concern could be related to a number of different areas of the Supplemental Restraint System (SRS). The weight sensor under the seat may not be reading a correct value. There could be an open or short somewhere in the...
What does the service engine soon Warning Light mean?
The service engine soon Warning Light is located on the instrument panel. This light illuminates solidly when the on-board diagnostics system (OBD-II) has noticed a malfunction. If the light is blinking, then the OBD-II has detected that the engine is...
Malfunction Transmission light appeared on dashboard
Automatic transmissions can be tricky. Luckily, as odd as it seems, the fact your vehicle is setting a warning light is a good thing. This allow you to run a diagnostic scan for trouble codes, and will help narrow down...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com