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Power shut off while driving

I have been having a problem with my car lately. Started out where the power lock/unlock wouldn’t work when the car was turned off. Then it would work again. then yesterday, my radio kept turning off and then back on, then the Park, Reverse, Neutral,Drive display started flashing. Then all the gages started moving crazily and then NO power. My car just shut down on me. I pulled it over, turned it off and sat for a while. then restarted it just fine, and drove home. Any ideas why my car keeps doing this?

I suspect the ignition system is acting up.

A test of it should be done.

Get two or three opinions though.

My 2001 Malibu is starting to act like yours! First, sometime last winter it stopped honking when I hit the lock button on the key fob (it still locked). Then it would randomly honk or not, then the lock on the key fob stopped working. I lock it manually when I get out of the car (engage it before I shut the door) and it honks every time.

Then, just the other day when I started it up, a strange, somewhat random beep sounded. No idiot lights flashed, but I noticed my seat belt wasn’t entirely engaged and figured that was it (note- I’ve NEVER heard the beep before and it wasn’t like the chime when I haven’t put on my seatbelt at all).

When I got home (drove less than 5 miles) the door remained locked when I turned off the car and I noticed that the lock button was in between lock and unlock. Now it doesn’t unlock when I turn off the car, but it locks when I engage the transmission (as usual). Hmmmm. Ghost in the machine??? Did I fry something when I drove with the lock misengaged??

Anybody else have a quirky Malibu around 80K miles?

Since you did not share either the model year or the odometer mileage of your Malibu, diagnosis from afar will not be as accurate as if you had provided the missing information, but, regardless, here goes my best guess:

I believe it is likely that the brushes in your alternator are worn out and that you are getting wildly fluctuating voltage output. This type of situation will take place for a very limited amount of time (a few days perhaps) before the alternator finally dies. If this is what is happening with your car, and if you ignore it any longer, two things are likely to happen–you will kill the battery, and you will wind up being stranded.

If your Malibu is of recent vintage, or if it has less than ~50k on the odometer, then the above-noted situation is unlikely.

Could be several things, start with the simple stuff first. If the car is over 3 years old it could be a bad battery, perhaps one cell is gone and the battery is providing low voltage. It might have enough to start the car, but another cell will fail soon and then you’ll be stuck. Get the battery checked.

Next, is the alternator might not be charging a good battery fully. This could be the whole alternator is shot, or the rectifier, or voltage regulator. These components are integrated into some alternators so you have to have the charging system checked.

If the battery and alternator are both good, then things can get interesting. Next item to check is the ignition switch itself, then the security system, then …