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.


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