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2009 Corolla Intermittent Electrical Issues

Help! My wife’s 2009 Toyota Corolla is possessed and it’s gotten her so frustrated she brought home a new puppy two days ago.

Over the last two weeks we’ve noticed a handful of times, after we’ve turned off the car and left it (with the interior headlight control in the off position) that we’d go out to the garage only to find the car’s headlights on. (Keep in mind, it has a sensor that will automatically activate the headlights in dim light but this only is supposed to happen when the car is on.) It began having issues starting and yesterday it wouldn’t turn over. Yet, when turning the ignition, it made a sound different than I’ve heard on the car when it has a dying/dead battery. Before calling the tow truck, I tried jumping it. The car did turn over – and the headlights immediately came on (might have been the sensor in the dark garage, but they come on almost immediately rather than after a brief delay). Yet it died quickly after and wouldn’t start again. My neighbor, however, smelled gas and suggested the engine might be flooded.

The car was towed to my mechanic – who’s a good guy. He just called and said the car turned on for him without a problem and he can’t find anything despite running a battery of tests. He said he just doesn’t want to swap stuff out without knowing there’s an issue.

So, what could possibly be causing the car’s headlights to go on when the car is completely turned off and the internal knob for the headlights is also in the off position? And could it be related to the car not turning over – or did my wife flood the car when she tried to turn it over yesterday morning, creating a wholly separate issue?

Thanks! -CB

This is one of the extremely rare circumstances where I’m going to suggest taking it to the dealer. It’s going to take an understanding of the lighting ciruit schematics to troubleshoot this. It’s probably going to be a bad relay, but these circuits con go so many different places that it can be hard to guess.