Q: My check light came on possibly due to battery corrosion and poor electrical connection

asked by on July 18, 2017

My check engine light popped on Saturday night. We have had NO problems, good upkeep. I popped the hood checked the battery under the sheath and noticed severe corrosion on the negative end. I cleaned it with baking soda and water and the check engine light went off. 2 days later it popped back on. Did I find the problem and do I just need a new battery and negative wire? Or do I need to pay $100 on top of that for the exact diagnosis codes?

My car has 94000 miles.
My car has an automatic transmission.

Hi There, Generally, the check engine light comes on when something fairly serious is going on with the vehicle. If the problem were related to an electrical voltage problem, the charging system light will usually come on.

The check engine light may come on for many different reasons such as a faulty mass air flow sensor, a faulty O2 sensor, a bad catalytic converter, bad spark plugs or spark plug wires and many other reasons. Due to the wide range of possibilities for the check engine light to come on, the best and most efficient way to narrow down the scope of what may be causing this is to have the vehicle hooked up to a scanning tool to download any potential fault codes that may have registered in the computer. This will allow a mechanic to determine more specifically what to look for in diagnosing your vehicle. I would recommend having an expert from YourMechanic come to your location to take a look at your vehicle to determine what may be causing your check engine light to come on.

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

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