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Battery Won't Hold Charge After Disconnecting/Reconnecting

Hi,

I have a 2006 Pontiac Vibe. Yesterday my Check Engine light came on while driving. It’s done this before and randomly gone away. My car has been in the shop twice in the past month for routine maintenance and no issues have been found.

The light annoys me, so I disconnected the battery and reconnected it a few minutes later. The car wouldn’t start. I jumped it. It started, I let it idle, turned it off, and it’s dead again. I did the same once more. Still dead.

So, my family “mechanic” says I probably didn’t connect the terminals well enough, and that it might just need to be adjusted (in all fairness, I’m playing the stupid girl card here). He said worst case scenario is that I randomly need a new alternator (I doubt this based on the circumstances), and it’s possible I might need a new battery (I think I replaced it three years ago, but maybe I didn’t).

Other ideas?

@NCGrace you’re not doing yourself any favors by attempting to get rid of that check engine light.

The fault code may point to a serious problem.
It could be as simple as a bad oxygen sensor.
Or it could be a faulty crankshaft position sensor.

You should at least get the codes read.

The light is not there to annoy you, but to warn you that something is going on.

The original plan was to take to AutoZone to get the code checked regardless of the light staying on or turning off. But apparently I have a different problem at this point.

You may need to fully charge the battery so see what’s what. Then drive it to autozone to have them check the codes and the charging circuit.
Don’t let them fix the car, though.

Report back with the results.

Much appreciated. We had a pretty nasty cold spell here for a few days, and I’m wondering if that murdered the battery. I’m going to get it jumped over lunch and go straight there.

It could. Cold kills the cranking power of a battery.
Often, when a battery has been allowed to run down, its capacity will not be what it was. It being three years old, that could also factor in. You may just need a new battery.

The next time you start the engine, bring the idle speed to 2000 RPM’s for 10 seconds This will allow the ECU to regulate the voltage to the battery again.

Tester

There could be any of 3 things wrong:
-You didn’t tighten the battery terminals enough or there is corrosion that needs cleaned off.
-The battery is failing
-The alternator could be failing.

A simple test that is usually done for free by places that sell batteries can tell you the story. A note: If the way it is failing when you turn the key is the whole car–lights, everything just goes dead completely like shutting off a switch, this is a good indication that there is corrosion on the battery terminals or you have a loose connection. You can try taking the battery cables off–negative first, then put the negative back on last–and cleaning the terminals and the battery posts and see if this helps. A wire brush will remove corrosion and a solution of baking soda and water is good for flushing away and neutralizing battery acid on and around the terminals. Wearing a pair of cheap safety glasses when working on a battery is a good idea too.

Good luck!

Fixed! I used a makeup brush and cotton swabs to clear the corrosion, screwed those babies on tight, and it started right up. I’m still taking it to Advanced to have them test the battery. Thank you everyone!

Great! Thanks for the update. Glad to hear it was a cheap fix.

"Fixed! I used a makeup brush and cotton swabs to clear the corrosion"

McGuiver’s long lost daughter has finally been found. Good work.