Battery Test Question
Thread Starter
Pro
Joined: May 2004
Posts: 656
Likes: 38
From: Midwest
St. Jude Donor '08
Battery Test Question
I have an older battery that I recently had tested at the local parts store.
I keep the car on a trickle charger.
The battery tested fine.
When I took it to the store, it was fully charged from the trickle charger.
Is it possible to get false battery test results since it was just taken off the charger and fully charged?
Would I get a more accurate reading if I have it tested after not being on the trickle charger for 3-4 days?
Thanks,
Silverbird
I keep the car on a trickle charger.
The battery tested fine.
When I took it to the store, it was fully charged from the trickle charger.
Is it possible to get false battery test results since it was just taken off the charger and fully charged?
Would I get a more accurate reading if I have it tested after not being on the trickle charger for 3-4 days?
Thanks,
Silverbird
Burning Brakes
Joined: Jun 2017
Posts: 1,045
Likes: 275
From: Wichita Falls Texas
I agree with 8VETTE7.
Older batteries scare me. If I was having doubts about it I would get rid of it and buy a new one.
I hate it when a battery fails. You just cannot prepare for it other than carrying a bunch of stuff with you.
Peace of mind to me is important.
Good luck!
Older batteries scare me. If I was having doubts about it I would get rid of it and buy a new one.
I hate it when a battery fails. You just cannot prepare for it other than carrying a bunch of stuff with you.
Peace of mind to me is important.
Good luck!
Instructor
Joined: Jun 2013
Posts: 104
Likes: 20
From: Akron Ohio
I had a similar experience as 8VETTEZ with my 1999 convertible. I'm embarrassed to admit that I may have lived with it for five years.
I bought the car from a dealer who was selling it on consignment in 2013. The car would not start the first time I looked at it. They charged the battery and it started fine. A few days later I went back to look at it again and again it wouldn't start. I ended up buying the car but I insisted they install a new battery which they did.
After that I had no problems with the car if I drove it every few days. If I let it sit too long it would not crank. I assumed there was a parasitic draw somewhere and I read a lot about the issue on this forum but I never did anything about it. Finally, after taking it out of storage this spring, the battery would not hold a charge. I bought a new battery and, since then, the car can sit for two weeks and will still start. I suspect that the new battery the dealer installed was questionable from the start.
I bought the car from a dealer who was selling it on consignment in 2013. The car would not start the first time I looked at it. They charged the battery and it started fine. A few days later I went back to look at it again and again it wouldn't start. I ended up buying the car but I insisted they install a new battery which they did.
After that I had no problems with the car if I drove it every few days. If I let it sit too long it would not crank. I assumed there was a parasitic draw somewhere and I read a lot about the issue on this forum but I never did anything about it. Finally, after taking it out of storage this spring, the battery would not hold a charge. I bought a new battery and, since then, the car can sit for two weeks and will still start. I suspect that the new battery the dealer installed was questionable from the start.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,600
Likes: 4,059
From: Cape Coral, Florida
Hello !!
You said you took the battery off the trickle charger and had it tested. The test is NOT done on a fully charged battery !!...Did you remove the “surface charge” before testing ??...you HAVE to or you will not get an accurate reading from the load tester. I turn on the headlights for a few minutes to remove this surface charge. If you don’t a weak battery will test normal !!
You said you took the battery off the trickle charger and had it tested. The test is NOT done on a fully charged battery !!...Did you remove the “surface charge” before testing ??...you HAVE to or you will not get an accurate reading from the load tester. I turn on the headlights for a few minutes to remove this surface charge. If you don’t a weak battery will test normal !!
Last edited by C5 Diag; Aug 11, 2018 at 08:49 AM.
