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Q: Backlighting to the dashboard failed now it’s distracting

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I have a problem with the dashboard in my 2009 Chevrolet Malibu. The light behind the dash randomly gets brighter and then dimmer, then brighter again, and so on. The car has just 35,000 miles on it, so I didn't expect a little problem like this to pop up. What could be causing it?

A: This actually may be a normal condition. Th...

This actually may be a normal condition. The alternator on your car has a specified amount of amperage it can output at a given engine speed. For instance, your alternator's maximum output is approximately 125 amps, but only 85 amps when under load. What this means is, that if your car has all stock parts and no aftermarket electrical items running, your alternator should have no issues above high engine idle speeds. If you only notice the problem when the engine is at idle speed with heavy accessory loads such as: lights on at night, A/C on medium to high blower speeds, or the radio on and phone plugged in, the dash lights may dim when you are stopping or at a stop due to the heavy electrical loads on the alternator. It is causing a brown out, much like those in our houses when the electric company cannot put out enough power for the demand we need. Your car may be doing the same. This is normal if your battery and charging check out fine and all tests are ok. I recommend contacting YourMechanic for a system check.

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