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Q: Fuel light flashes, check engine light on

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My car has recently developed an issue with the fuel light that started flashing for no apparent reason. This occurs while I'm driving with about half of gas tank or more. The fuel light starts to flash, which is followed by the check engine light coming on as well. I had the fuel cap replaced. What might cause this?

A: Hi there, thanks for writing in about your ...

Hi there, thanks for writing in about your 1997 Mercedes-Benz S420. The fuel light circuit receives information from the fuel level sending unit to show the approximate fuel level and give a warning as the level becomes low. There can be a malfunction in the sending unit circuit or the circuit for the lighting. I recommend having an experienced technician diagnose the warning lights in order to make the appropriate repairs.

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