Recently, my family purchased a new(er) vehicle and we’re trying to sell our old 2003 Chevy Trailblazer. It had some minor transmission work done to it about 4 months ago, right around the time we bought our new vehicle. I’ve started it up and drove it about twice since then so it doesn’t sit too long (I honestly let it sit about 2 months between last drive and now).
However, we finally had a buyer, but when I went out, I got NOTHING. The key even got stuck in the ignition, because it requires even the slightest bit of electricity to release the key lock.
I took the battery down to the auto parts store to get it looked at and they confirmed it was dead, but that the cells were fine. They recharged it for me. I took it home, hooked it up, had power just fine. Drove it around, tested A/C, etc, key came out, everything hunky-dory.
Person showed up the next day to look at it. Dead. Dead-dead. Key stuck in lock again, dead.
I’m trying to think of what changed in the last two months, and what could have drained a recharged battery in 24 hours. I appreciate any assistance, as I will have to have the car towed to a mechanic to get fixed, which will probably end up being half of what we wanted for the car anyhow!
I can certainly do that, but is that more treating the symptoms than the problem? Would a person expect a brand new battery to get sapped quickly as well?
If that 2 year-old battery went completely dead, it needs to be replaced anyway.
Starting batteries aren’t deep cycle batteries. When a starting batteries are deeply discharged they never hold a charge properly or their reserve capacity.
Besides, in order to troubleshoot a possible charging system problem or a parasitic draw problem, you need start out with a known good battery.
Personally, I wouldn’t replace the battery until I ruled out a parasitic draw problem. If discharging them completely damages them and yours discharges overnight (which is plausible for even new, fully charged batteries if the draw is sufficient), then you risk damaging a perfectly new battery.
Checking parasitic draw is not hard and can be done pretty quickly. Even a damaged battery can deliver enough current to check parasitic draw.
Many possible sources of draw on your truck. For example a few years back, I had a dead battery in my 05 TB one morning. Charged it back up, checked alternator output and it was fine. Drove around the block and parked it. Next morning, dead again. Recharged and started parasitic draw testing. Found excessive draw after computer went to sleep (a few minutes). Started pulling fuses and eventually found it was a resettable fuse for power seats. I left it out and drove a few days without incident. Fixed next weekend, failing seat switch. Never did replace that battery. Lasted until I sold it about a year ago…
Just get a new battery. Same thing happened to me on a 1 year old battery. Charged it for 24 hours and wouldn’t even run the starter. Had to get a new $70 battery to deliver it to the buyer that was paying $50. Sometimes you just have to do what you have to do if you want to get rid of it. Batteries do not like to sit. Put a maintainer on the new battery if nothing else.