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Q: P0420 code and dash lighs on

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The dashboard in my car shows check engine light and VSC light illuminated, along with the P0420 error code. I soon have to take the emissions testing so I would like to get this fixed, Could you please tell me if this is a serious issue and if it is going to be expensive to fix it? Thank you in advance.

The vehicle stability control (VSC) light and code P0420 are for two different problems.

The VSC system would need to be tested for codes for that system.

The code P0420 is for the O2 sensor or problem with a catalytic converter problem and would need further testing of the sensor to see what is the cause of the code.

Only further diagnosis of the Check Engine Light can narrow the problems down for you.

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