Power draw from battery when truck is off

I'm having an electrical problem with a different car, and decided to check the Sequoia as well, just for reference.

I put a clamp meter on the battery lead, and it shows almost an amp of power draw. Isn't that really bad? Or is that normal with all the computer BS in there now?

Should I be looking for a problem to fix? Or should I shop around for a battery disconnect switch?

Have you measured how much power your car uses when it's off?

 

1 amp is a lot for a parasitic draw..
Typically, the normal amount of parasitic draw is between 50 and 85 milliamps in newer cars and less than 50 milliamps for older cars.
Mine is around 30 milliamps and I have a remote start/alarm that is always on.

How to Find a Parasitic Battery Drain: 11 Steps (with Pictures)

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I guess I gotta go pull a buch of fuses to figure this out... I wish it weren't so cold outside, my fingers freeze in a couple of minutes.

 

Some computers have to be turned off for hours before the draw stops.

 

My draw was diagnosed here: https://www.tundras.com/threads/tun...arasitic-draw-with-potential-solution.154738/

 

Well, if 0.1A is a problem... I must have a problem

Though I should check the draw again after the truck's been off for a couple of hours, I wouldn't be surprised if it takes that long for the computer to go to sleep.

 

There is a BIG difference between 1 amp and 0.1 of an amp.
Are you sure the battery is good?
I'm currently having an issue with my battery losing around .5 an amp overnight.



I let it sit overnight and tested the draw and it was between .25 and .30.
The battery loses a 1/2 volt overnight whether it is disconnected or connected in the truck.
I'm not driving it every day right now so if I don't start it every 2 days I have to jump it.

It is still under warranty with Interstate, but the problem is they want to keep it overnight to test it.
That is a problem for a few reasons.
1. Because of shoulder surgery, I can't lift the battery out of or back into the truck.
2. I have no vehicle to run to the store and back the next day if I could lift it
3. I'm not leaving my truck in their parking lot overnight and having them pull it.

So I'm keeping records and documenting this stuff in hopes they will swap it without the 24-hour hold.

My cheap battery tester has helped a little.

$30 KONNWEI KW208 12V Car Battery Tester, 100-2000 CCA Load Tester Automotive Alternator Tester Digital Auto Battery Analyzer Charging Cranking System Tester for Truck Marine Motorcycle SUV Boat

Amazon.com: KONNWEI KW208 12V Car Battery Tester, 100-2000 CCA Load Tester Automotive Alternator Tester Digital Auto Battery Analyzer Charging Cranking System Tester for Truck Marine Motorcycle SUV Boat : Automotive

It has only come up once as a bad cell.
It usually says the battery is good but it needs to be recharged.


Cranks low after sitting all night.


Charging system is fine.

 

If your battery drops to 12.2V overnight while it's disconnected: it's no good anymore. I hope you find a way to get the warranty replacement!

 

The resting voltage of a battery cannot be measured until about two hours after any type of charging, including float charging. I suspect 12.2 is the resting voltage and you are getting the 12.6 right after shut down. Most batteries read about.3-.4 higher than resting after shutdown. It is just the nature of lead acid batteries.

 

The 12.6 is after a start and 15-minute run.
The 12.2 is in the morning as I lay in bed, looking at Drone app, not doing anything to the truck in the driveway.
If I wait 2 days without a start, it would drop to 11.8, but start.
3 days drops to 11.3 and won't start without a jump.

It does the voltage drop whether the battery is connected or not.
I know the battery is bad, I just don't know if they are going to take my word for it without the 24-hour testing bullshit.

If not, I'll just have to buy a new battery and let them test the old one.
If it's bad and they replace it under warranty, I'll sell it.
I don't need 2 batteries.