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Battery light blinking

I just got new tires today, and on the way home I noticed the battery light blinking on and off. I had also scraped a parking log that was broken in half and in the wrong place about the same time. What is this a coincidence? I need to drive over a mountain pass and am hesitant to get far from car help.

Wanted to edit: Could either of these events cause this problem or is this a coincidence?

I would not be driving in the mountains before I found out what that brake light is. Many years ago I was coming up on a mountain pass on a Sunday, in winter with snow when my brake light came on. I stopped at a motel. It turned out it was just moisture in an electrical connection and had no connection with the brake operation, but I was gad I did not go on.

Yours may be little or nothing or it may be a serious safety problem.  

Assuming you have the owner's manual it should tell you want that blinking light means. I suggest you check it.   It would also help if you could tell us what make model and year car you have.  

OOps I better get my eyes checked I read that as “Brake light flashing.”

have you looked in your owners manual for what a blinking battery light means?

off hand i would suspect the battery system is going (or failed) a load test at your local mechanic could help pinpoint possibilities.

have you looked under the hood???

are the battery connections tight and corrosion free?

call the tire place. ask if they disconnect the battery for any reason when doign tire changes. is the tire change ALL that was done?

The battery light rarely (never?) indicates a problem with the battery. Instead, it indicates some sort of problem with the charging system (alternator, diodes, voltage regulator, wiring, etc.).

If the light at a fixed interval (i.e. twice per second or something), then the computer is trying to tell you something and you should probably have a mechanic check it out. Some chain stores will test a battery & charging system for free, others it is usually less than $10.

If the light is blinking “randomly” then it is possible that the parking log broke a wire underneath somewhere, and this probably won’t be too hard to fix at a shop with a lift (prob an hour labor at most).

It is unlikely, but not impossible, that the shop damaged your charging system when you got your tires. Some shops will do a check on every car that comes in the shop, which usually includes a quick check of a few things under the hood- if they accidentally damaged something when they did this check then the shop would be responsible, but I can’t imagine how it would have happened. I suspect the parking log thing more.

What kind of car?

You have an issue with your charging system. Get this addressed closely and soon as possible. Don’t be surprised if you sputter out on the side of the road due to lack of battery/alternator power which is required to run a modern vehicle.

There may be a connection with the events. The vibration from the hit may have disturbed a loose connection in the charging system somewhere. I suggest you clean your battery connections, make sure the fan belt to the alternator is good and snug, and also check the wire connections to the alternator. Make sure they are clean and tight.