Battery drain standby 1.2 Amps - normal?

[lion2000]

Since I changed my work, I do not drive my 2001 X5 every day (once/3-4 days), the battery died. I replaced the original battery. 2 months later, the new battery died. Then I got my third battery, it then died in 1 month. What appears to me is the following:

1. The brand new battery is fully charged, and it takes a while to drain all the charge. So the first dying event occurs after 1 month.
2. Since I do not drive much, even once 3-4 days, the battery can not be charged to full each time after driving. It dies more frequently.
3. I measured the battery current drain (with all interior lights off and engine shut off). First minute turning off the engine, it is ~2 Amps. After 1 minute and on, it is 1.2 Amps. At 1.2 A of standby current, it may be too much for the battery.

My question is that anyone knows is 1.2A current too much as standby current? Is the new battery permanently damaged when charge is completely drained?

Thanks, //leo

[dkl]

How much is it draining after 20-30 minutes? It has not gone into sleep mode yet after just a minute or two.

[Weasel]

After 16 minutes it should be in full sleep mode and should draw no more than 38 miliamps. (0.038 amps) The best way to measure this is with a low amp inductive amp probe that clamps over the ground wire, and viewed with a graphing oscilloscope meter.

[lion2000]

Thanks for the quick reply, much appreciated!

After 20 minutes, the sleep current went down from 1.27A to about 1A (the light at transmission turned off). According to other posts, it should be 0.038A. Looks like the next step is pulling the fuse to see which circuit is causing the excessive draw. I will update with the result.

[lion2000]

My garage was hot for a few days. Today it was cool so the work continued.....

I pulled out fuse #27 that shuts the interior lights off. I placed a meter between battery cable and the body chassis. After starting the car and let the battery to be charged for 10 minutes, I shut the engine off. I disconnected the battery connection to the body with the Amp meter intact. I then shut all doors. The current went down to 1.05A. After a minute, it went down to 0.52A. After 15 minutes, it went down to between 0.05-0.07A (flutuates) in sleep mode.

I then retored fuse #27, turn ignition key to 1, 2. then off. Shut all doors. The current behaves the same way.

Mysteriously, I do not see 1.2A sleep current anymore. All I did was (accidentally) disconnect and reconnect battery multiple times. All I can conclude is that something is not reliable, this problem may appear again someday.

//leo

[motordavid]

In the meantime, cop a Battery Tender or one of its cousins, for less than $50,
alligator clip it to the terminals under the hood, and keep your current batt
charged up. It takes about 30 seconds to hook up/unhook when you need to
drive.
GL,mD

[dkl]

Especially if your X is garaged. Just hook up a battery tender and let it charge overnight every once in a while.

[lion2000]

Great idea! Thanks so much.

[X5 Meister]

That's a pretty high load. Note that the BMW battery tender charges at 1.25A