Load testing a battery when cold vs hot:

[Carnoobie]

Originally Posted By: hemitom
You know what! Leave the headlights on overnight kill the S.O.B so its stone cold dead and bring that back to them test .


But cant you tell if the battery was intentionally drained? Probably wouldnt be good for my charging system either leaving lights on.

Originally Posted By: yonyon
Do you no longer live with your parents? Do they no longer drive?


Dad does but hes away for the night. I dont feel comfortable having my car sit in a deserted dark lot alone either. Maybe i will go there 1am and sleep in the car til they open. All depends how bad i want to save the $100. But like i said, theres no gaurentee that ill even have a new one, i would be so [censored] if i didnt.

 

[hemitom]

No way for them to prove it, will not affect the charging system whatsoever.

 

[yonyon]

They can tell the difference between a discharged battery and a kaput battery, but if a battery is discharge and left in very cold weather it will freeze and become a kaput battery. This, however, would be dishonest and unscrupulous on your part unless you could be completely sure beforehand that the battery is indeed faulty.

 

[hemitom]

They cannot prove it they may suspect it, and with these tools you will have to fight to get it replaced.

 

[hemitom]

Dishonest unscrupulous these quick lube joints are the masters of dishonesty i wouldn't lose a wink of sleep over it.

 

[Carnoobie]

Hmm interesting. Well if i did this, i would have to drive there at around midnight tonight and sleep in the car til 8am. Am I willing to do this? Any thing less than 8hrs of my car sitting and I take a chance of it not being 100% cold. Just from my past experiences and what i notice.

I really do mean it when i say these are the biggest morons working there. It makes me upset just having to see them. But the other piece tells me to forget it with these idiots and never go in there ever again and just go buy a new battery tommorow and cough this up as a bad experience, even though its WRONG!

 

[yonyon]

Well there you go. Assign weight to each of {wrongness; coldness; $100} and choose your course of action based on that. When you're done, regardless of how it works out, be confident that you did what you did for a reason. If you're not happy with the results go ahead and use that to help guide you in the future, but don't be troubled over it.

 

[Carnoobie]

Originally Posted By: yonyon
Well there you go. Assign weight to each of {wrongness; coldness; $100} and choose your course of action based on that. When you're done, regardless of how it works out, be confident that you did what you did for a reason. If you're not happy with the results go ahead and use that to help guide you in the future, but don't be troubled over it.


Well at end of the day I dont trust the idiots there, that includes the 19 year old manager running the place.

-10 is cold and with no heat. Theres not even a gaurentee ill be able to get a new one, infact I dont trust them for anything. I could sleep there for 8hrs and then ask them to do a test with my car just right outside their bays and they could refuse "its too cold out, car needs to be in shop blah blah blah" Going by my experience, I can tell you they will not do the test with the car outside, so much for that testing with the cold start, right out the window.

I could just forget about it and buy a new battery tommorow from Costco that comes with like 9 year warranty I hear. Only downfalls of this are, I dont even know 100% forsure its the battery, so i could be replacing it and blowing $90 or whatever for nothing. its a gamble I take, but you know what? This mech probably is right. It most likely is the battery.

Ive had 3 people tell me (from what I told them) its the battery. Obviously the forsure way to tell is put a new one in.

And for the mech who offered to do the cold test for me tommorow morning on my driveway with his smart meter. Ya not for $60, [censored] no. I understand its going to be -10 out, but $60 for 10mins? Cmon

 

[JimPghPA]

1) Do you have access to a set of jumper cables?

2) Do you have access to a second vehicle that can be parked close enough to your vehicle so you can tie the battery of the other vehicle with yous via the jumper cables just before you try to start your when it is cold?

If both answers are yes, than tie them together so you can then try to start your with plenty enough battery capacity so if it still cranks slow it is the starter, and if it cranks fast it is the battery.

 

[Carnoobie]

Originally Posted By: JimPghPA
1) Do you have access to a set of jumper cables?

2) Do you have access to a second vehicle that can be parked close enough to your vehicle so you can tie the battery of the other vehicle with yous via the jumper cables just before you try to start your when it is cold?

If both answers are yes, than tie them together so you can then try to start your with plenty enough battery capacity so if it still cranks slow it is the starter, and if it cranks fast it is the battery.


Unfortunately I dont to either. Im useless.

Im probably just going to end up buying a new battery in the morning and take a gamble. But if im paying a mech $60 to come see me at my place in this -10 weather, I might as well just put that towards a new battery.

When I turn the key, the engine turnsover. Though sounds like dying cat. But its the EXACT same sound i got when my previous battery froze to death on me last year and had to boost the car to get this new battery I have in now.

 

[Carnoobie]

Hey whats the min. Voltage a car battery should have with car idling but A/C off? I got 12.62V and was told it should be 13-14 and my alt isnt charging the battery fuly.

Mind you, I had my amp, sub and deck still plugged in, but had the volume off. Not sure if that would be the difference.

Wondering maybe i should get my alt tested tommorow before i go buying a new battery?

 

[JHZR2]

That is sort of low. It's about ok to neither charge or discharge the battery. When you take it up to 1500 rpm, does the voltage rise?

 

[Carnoobie]

Alright just did alt test! or wait, was this a battery test that I did? im confused

Well surprinsingly, the car after sitting for 8hrs and stone cold (but plugged in), didnt slow crank at all, it started right away. Still cant tell if the block heater is working though.

12.49V with car off
Started car, showed 14.52 then dropped to 14.49 and then 14.39 when turned headlights, stereo on, and hovered around 14.39.

Originally Posted By: JHZR2
That is sort of low. It's about ok to neither charge or discharge the battery. When you take it up to 1500 rpm, does the voltage rise?


Ah sucks, just turned the car off, didnt do the 1500rpm throttle. I did yesterday though when we did a full load test and it says on the sheet

Battery results:
12.62V
476CCA, rated 500CCA

But im not sure if the Battery results is with the car on or off!

Then has:

Starter test: (dont forget on hot car)
11.22V
2.13S

Charging system test:
No Load: 14.3
Full load: 14.16 (with headlights on, throttle, full heat)
14.3V no load and 14.16V loaded (throttle, headlights, heat full).

 

[The_Jeff]

That slip sounds like something a Midtronics tester would generate. They are the world standard. They have a little infared temp sensing port and at the start of the test the operator is supposed to point it at the battery and get a case temp. This compensates for its internal resistance that varies with temp.

Said midtronics tester is pretty idiot proof and will actually detect electrical noise from a modern car's ignition and demand that you turn the key off for its initial test.

It sounds like, from over the internet of course, your battery is good and your starter is dragging. Could also be cables, connections, etc. Starters do sometimes drag right before they konk out for good.

 

[Carnoobie]

Originally Posted By: eljefino
That slip sounds like something a Midtronics tester would generate. They are the world standard. They have a little infared temp sensing port and at the start of the test the operator is supposed to point it at the battery and get a case temp. This compensates for its internal resistance that varies with temp.

Said midtronics tester is pretty idiot proof and will actually detect electrical noise from a modern car's ignition and demand that you turn the key off for its initial test.

It sounds like, from over the internet of course, your battery is good and your starter is dragging. Could also be cables, connections, etc. Starters do sometimes drag right before they konk out for good.


What makes you think the starter is dragging?

Whats the best way to test the starter? And does it matter if i test it when the car is cold vs hot?

12.49V for battery with car off with volt meter and 1262V for batter with car off with load tester.

Should i go run out and buy a load tester and do it myself?

 

[johnachak]

It only has 476 out of 500 CCA's? That sounds too low to me. That is supposed to be a minimum rating. I haven't bought a battery in at last 15-20 years with lower than 550 CCA to allow for cold overnights.

If the battery is rated at 500, shouldn't a lower reading be considered a failure? Does it have to be completely shorted for them to decide it's N.G.?

 

[Carnoobie]

Well John that 476 might have been when car was off. Im guessing it was.

When you do a starter draw test, in my case does it matter if the car is hot or cold? Mech says it does not. I need to know cause if it does not matter then ill take it to them today.

 

[Vikas]

Quote:

Starter test: (dont forget on hot car)
11.22V
2.13S


Anybody wants to explain this reading? Two point thirteen second of cranking is a L O N G time (especially on a Honda)! But holding 11.22V during cranking and 476 CCA tells us that your battery is fine. If it is indeed taking over two seconds of cranking to start your vehicle, you need to find a cause which will be something different than the battery or the starter given the current data.

Do you have a voltmeter or are you borrowing it? Hook up the voltmeter to the battery and record it using your cellphone video when you are trying to start the car while cold.

Either the car is not getting the spark or the fuel during the 1st couple of seconds if it is not starting. If you have a timing gun or inline spark tester, you can find if you are getting the spark during the cranking or not.

 

[Carnoobie]

Originally Posted By: Vikas
Quote:

Starter test: (dont forget on hot car)
11.22V
2.13S


Anybody wants to explain this reading? Two point thirteen second of cranking is a L O N G time (especially on a Honda)! But holding 11.22V during cranking and 476 CCA tells us that your battery is fine. If it is indeed taking over two seconds of cranking to start your vehicle, you need to find a cause which will be something different than the battery or the starter given the current data.

Do you have a voltmeter or are you borrowing it? Hook up the voltmeter to the battery and record it using your cellphone video when you are trying to start the car while cold.

Either the car is not getting the spark or the fuel during the 1st couple of seconds if it is not starting. If you have a timing gun or inline spark tester, you can find if you are getting the spark during the cranking or not.


But i have yet to do a FULL load battery test with the car cold. The one i did last night was with a volt meter.

Dont forget that 476CCA and 11.2V starter was done with the car HOT!

Yes I have a volt meter but was told that using a ful load batt tester is best no?


2.13S is from car completely off, key not even in first turn.

 

[The_Jeff]

Originally Posted By: johnachak
It only has 476 out of 500 CCA's? That sounds too low to me. That is supposed to be a minimum rating. I haven't bought a battery in at last 15-20 years with lower than 550 CCA to allow for cold overnights.

If the battery is rated at 500, shouldn't a lower reading be considered a failure? Does it have to be completely shorted for them to decide it's N.G.?


No! Midtronics believes (IIRC) 60% of new is useable. The little thermal paper printout gives a health update.

A civic with a gear reduction starter and 4 little cylinders probably only needs 150-200 amps to start.

The more I think about it the more I think OPs car's starter just isn't drawing the amps, so the battery isn't dipping much, and it's turning over slowly.

I haven't seen the battery tester's start mode but it probably infers it from the voltage drop and boost afterwards.