service engine soon light is ON?

The Service engine light comes on when the PCM (computer) sees a system fault and when this happens the PCM will set and store a fault code and or codes. In order to know what has failed you will need to have a code scan done to retrieved the fault codes and or codes. Most part stores will perform this scan for you at no charge. Once you have the fault codes and or codes then you can go for  correct repair. Removing the negative battery cable will clear the light but if you have a problem the PCM will at some point turn it back on.

This will help.

Thanks.

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