CarTalk.com Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

2011 Chevrolet Malibu - Auto Lights Off message

The car is a 2011 Chevy Malibu, with the current millage slightly over 71,000.

We recently vacationed in the southern part of the country. The weather was very warm to HOT. Traffic was terrible, with a lot of stop-and-go driving. I would often put the transmission in the manual mode, and use the “gears” and the engine to keep from having to apply the brakes so often.

Returning from one of our tourist trips, I stopped at a store, and left the car running with the air conditioner on (my wife remained in the car). When I returned to the car, I noticed a message at the bottom of the speedometer: Auto Lights Off.

I though it strange, but started the 4-mile drive to our motel. Along the way, I noticed that the blower and the air conditioner indicator lights were dimmer than they should have been. The air was also not as cool as it should have been. I turned off the air.

We got to our motel. I shut off the blower, and then the engine, waited about a minute, restarted the car, turned on the blower and the air, and everything was working.

The next day, after again driving in the manual mode, the Auto Lights Off message came on during the return trip, but the air was okay. After that, I decided to drive the car in the D mode, and did not have any problems. The 900-mile trip home was uneventful (except for the road construction!).

A week later (driving in D mode), I turned off the air as I began a merge onto an interstate from a short ramp during rush hour. I merged into traffic, and was still accelerating when I turned on the air. Both blower and air indicator lights dimmed. I shut the devices off. When I exited to a city street about 20 minutes later, I turned on the blower and the air—and everything was working.

Since we were going to make another trip (round trip being a little over 800 miles), I thought I should have the car checked out. My mechanic kept the car for a day, drove it, turned all the accessories on (I told him to beat it up) but could not duplicate the problem. The alternator and the battery checked out fine.

Any thoughts?

John

P.S. The problem has not occurred since, and the 832 mile round trip went off without a hitch. Everything performed as it should.

Since putting the shift in manual mode triggered the problem, you should probably avoid doing it again. By using the transmission to slow down you’re putting unnecessary wear on it. New brakes are a lot cheaper than a new transmission. As for your specific problem, my guess is that something is drawing excessive current, which is why your lights dim and A/C blower slows down. If that’s the case, the battery and alternator can both be fine and you still have the same issue.

my wife’s 2012 will sometimes have the dash lights dim. I have yet to find an issue with hers, either.

I do question why you turn the a/c off to enter the highway? Is this of some sort of benefit?

and downshifting to save brakes is pretty pointless, unless you are on a serious downgrade and your car is full.

If you have yet to replace the a/c blower motor and the blower resistor, that may be a good place to look. It it up under the dash on the passenger side, and the resistor wiring is right out int he open where it can get kicked. These wires get hot already, and then if you have big feet up in there, this can cause some extra heat and draw on your system.