Starter issues with low battery only

Question

My daughters 2012 Mazda 3 broke down, would not start. The tow people apparently tried to jump it, it would not start. As some point they apparently had trouble putting it in neutral, there was some clicking (the details are very sketchy unfortunately, I was not there). The tow people thought it was the starter.

When I get home to look at it, first thing measured battery and it was 11.5 volts, so figured that battery was just low, so I attempted to jump start it, and it started right away. Was getting 13.5 volts at the battery terminals whilst running. Run it for a bit to charge it. After the battery was 12.6 on it's own. I did run a load test 500 CCA with battery removed, at the end it measured 12.5 V and apparently good. So I figure the alternator and battery are good?

The thing is, the car starts fine now as if nothing was wrong. I can start, stop, start... repeat. No issue.

My daughter said she had moved the GPS into the always on power plug the night before and had no prob starting, then before the issue occurred, has sat in the car for half hour with the car off, waiting, charging phone and music (probably cooling on too).

But I keep thinking about the starter apparently sticking and wonder if this could be simply down to low battery charge. In your experience, would a 100% perfectly good starter ever stick even with low battery? I am thinking that perhaps the starter is getting bad, but not bad enough to fail at all when on full charge.

As I'm new to this though, I don't want to remove/replace a perfectly good starter just in case, if these is expected behavior.

Answer 1

If cooling and music was on, they can consume some significant amounts of charge. Were the lights on? If so, that's even more charge consumed.

Old batteries don't die by reduced CCA, they die by holding reduced amounts of charge. So, music and cooling (and perhaps lights) for half an hour can definitely eat up your charge, especially if your battery is old. A GPS in the always on power plug consumes only very little electrical charge.

So, my answer would be that you don't need to be concerned about anything yet. If you don't like the fact that the battery holds only very little charge, do replace the battery. Eventually you'll have to replace it anyway.

Answer 2

The starter sounds fine, the clicking noise could be all sorts of things. If your starter was sticking, you'd know. The battery sounds like it is fine as well.

This just sounds like your daughter is using too much power without running the car. In the IT world we would call it "user error", I think some training would make more sense than replacing anything at this point.