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Does anyone happen to know off the top of their head what the power system should be drawing when the car has been off for 5 or 10 minutes?

Car wouldn't start yesterday, even though it's got a brand new battery. Tried to charge it with my battery charger to no avail, voltage kept jumping around. I had trouble finding a clean enough connection under the hood for the cables. Switched to jumper cables and my 2015 Silverado. Still wasn't seeing >12V at the Caddy end of the cable, and the car was only pulling about 4A through the jumper cables. Wiggled the clamps around a bunch and managed to get the juice flowing, current draw jumped up to 15A, and then the car started.

The new battery has been in the car a few weeks, and I've driven it intermittently since installation. No hint that it wasn't charging or that something was supposed to shut off that wasn't shutting off. Always got a decent crank, which wouldn't have been the case if the battery wasn't charging.

The only thing I could find that was "wrong" was the negative battery cable clamp. I put it on the post but apparently forgot to tighten the clamp. It wasn't falling off the post loose, but I could easily turn the clamp around the post with my hand. So I cranked that fucker down.

Took the car for a ride to Home Depot (parked nose out). Inside for 15 minutes. Car started right up again. Drove home and put the clamp ammeter on the battery lead after shutting the car down. After a few minutes, current had dropped to 200mA. But it didn't drop any further after 10 minutes. And that seems kind of high. If the battery has 70A-hours of capacity, 200mA will drain it in 14 days. I think I'm going to have to start pulling fuses to find what's drawing power.

But before I go through the frustration of that exercise, I thought I'd ask if anyone knows what the quiescent current draw is supposed to be.
 

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Does anyone happen to know off the top of their head what the power system should be drawing when the car has been off for 5 or 10 minutes?

Car wouldn't start yesterday, even though it's got a brand new battery. Tried to charge it with my battery charger to no avail, voltage kept jumping around. I had trouble finding a clean enough connection under the hood for the cables. Switched to jumper cables and my 2015 Silverado. Still wasn't seeing >12V at the Caddy end of the cable, and the car was only pulling about 4A through the jumper cables. Wiggled the clamps around a bunch and managed to get the juice flowing, current draw jumped up to 15A, and then the car started.

The new battery has been in the car a few weeks, and I've driven it intermittently since installation. No hint that it wasn't charging or that something was supposed to shut off that wasn't shutting off. Always got a decent crank, which wouldn't have been the case if the battery wasn't charging.

The only thing I could find that was "wrong" was the negative battery cable clamp. I put it on the post but apparently forgot to tighten the clamp. It wasn't falling off the post loose, but I could easily turn the clamp around the post with my hand. So I cranked that fucker down.

Took the car for a ride to Home Depot (parked nose out). Inside for 15 minutes. Car started right up again. Drove home and put the clamp ammeter on the battery lead after shutting the car down. After a few minutes, current had dropped to 200mA. But it didn't drop any further after 10 minutes. And that seems kind of high. If the battery has 70A-hours of capacity, 200mA will drain it in 14 days. I think I'm going to have to start pulling fuses to find what's drawing power.

But before I go through the frustration of that exercise, I thought I'd ask if anyone knows what the quiescent current draw is supposed to be.
I was under the impression that 2 weeks was about max for the battery on these without a tender.
 

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I was under the impression that 2 weeks was about max for the battery on these without a tender.
I have let my car sit with the original 2012 battery for 2+ months without a tender and it has been fine.

I know these cars sometimes have an issue with the door switch which causes abnormal current draw when shut off. That is generally the first place I would look.


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Above the battery, in the fuse panel there is a nut which supplies power to the panel that will come loose over time. For long storage, you can always pull the fuse for the computer. But test to make sure your key fob still works
 
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