Old dog learns new trick.

[Redcrown]

I backed my wife's car out of the garage to get to my cycle. Ten minutes later I tried to put the car back but it wouldn't start. It just made a fast clicking sound somewhere under the hood, and all the lights on the dash flashed in sync with the sound (and there are lots of lights).

I turned on the accessories and everything worked OK. The radio played, the fans blew, the blinker blinked. So I went to Google and entered "car won't start", and the first autofill added, "... with fast clicking sound." Obviously a common and well known symptom. That led to dozens of links that said the battery was bad. Enough power to run the accessories, but not enough to crank the engine. Sure enough, when I added jumper cables to my car, hers started right up.

Now, in my youthful days, when a car battery died it was a slow death, marked by slower and slower engine cranking. Apparently that's no more. Now you just get a laser light show with music. I'm wondering why one of those dash lights doesn't just say "low battery" like every other electronic gadget these days.

[Rhossydd]

I had the same happen to me a couple of months ago.
I think that the car continues to operate normally then hits a threshold and prevents the starter motor activation to prevent totally flattening the battery. A completely flat battery would be a big problem as the door locks and electronic ignition keys wouldn't work.

But yes, crazy that they don't have a low battery warning anywhere to tell you that the threshold has been reached.

[Robert Roaldi]

My rule of thumb used to be to change the battery after 5 years no matter what. I bought my current car new and I replaced its battery recently after 7.5 years. For the better part of the last 2 years, I have kept a booster battery in the car jic.  I'd hate to be stranded in the middle of nowhere when a battery fails, especially since I live in a region with harsh winters.

I agree that it would be useful if the car could keep track of the battery's health, but I have a feeling that's not entirely useful unless you have a dedicated battery that talks to your car's CPU and that would probably increase the price of a battery. I think this is the case with many camera OEM batteries.

A friend had to recently replace the battery in his BMW (not sure which model) and the new battery needed to be properly configured (not the word they used) after installation, something that could only be done at a dealer, he was told, and it was not cheap. He ignored the dashboard warnings about that and eventually the car's CPU and the new battery made their peace and are now getting along fine.