Battery Drain? - Page 6

crystalworks · #1 10-26-2020, 02:36 PM

Just to add one data point. New (aftermarket) alternator a few years ago and just installed a new battery in my 4.8is a couple weeks ago. Truck has been sitting in the garage (~78f constant) unlocked since 10/18. Battery voltage (ignition off, truck not yet asleep) measured at jump points under hood was 12.8v. Yesterday 10/25 battery voltage measured 12.26v, again under hood and truck "awake" as I opened the door to pop the hood.

Orange shift light turns off after ~15 minutes after last door closed when left unlocked. Don't know what it does when locking and the alarm is active. I stick a trickle charger on it last night after measuring voltage.

Don't know if that says anything about your situ, but it's data. Good luck, battery draws suck. EHC module put my 4 year old battery in the grave.

StephenVA · #2 10-27-2020, 09:22 PM

I believe some early models have the shifter light that stays on. Not on any face lift models just the early models

Purplecty · #3 12-27-2020, 02:40 PM

So the 4.6 is in hibernation for the winter still in a heated garage with the garage tstat set to 50F. I started the x5 last week sometime and today I went to do the weekly start and warm up and it is completely dead again. It's been fine until today. I will recharge the battery again and disconnect the kenwood aftermarket radio...

StephenVA · #4 12-28-2020, 11:26 AM

It can only be one of two things (if all the connectors are clean and tight)
1. Battery failing
2. Drain on battery even with the key in your pocket.

A cheap volt meter is all that is required to find Item #1
Item two is just a question of elimination. Circuit by circuit. Most failures are found in areas like Media players still running, Nav systems still running, door lights and switches turning on due to door wiring chaffing.
Here the quick questions is "Does that vehicle go into sleep mode?"

Purplecty · #5 12-28-2020, 04:14 PM

I will probably go with #2 as the car is properly going to sleep unless it is somehow waking up later on and staying awake. I feel that the last time I started it something either caused it to not goto sleep when turning it off ( I didnt check since I haven't had this issue since october) or something I.E blower resistor is potentially causing a random drain when the X is off (which is just an assumption without any real testing being done yet). The last time it happened, I fully charged and took it to advanced auto and the battery was tested as good. This has not happened since october 20th. I disconnected the air suspension module since the PO did a rear spring conversion and removed the BM53 that was already disconnected and no longer being used as the PO installed an aftermarket kenwood radio. Will this multi meter work? It's currently set to volts.

80stech · #6 12-28-2020, 04:32 PM

No, you need one that will measure DC current and preferably in milliamps, ---or big old school voltmeter with low internal resistance that you are familiar with. ---or use that voltmeter with an external shunt.

Purplecty · #7 12-28-2020, 04:35 PM

Quote:

Originally Posted by 80stech

No, you need one that will measure DC current and preferably in milliamps, ---or big old school voltmeter with low internal resistance that you are familiar with. ---or use that voltmeter with an external shunt.

Any links to a decent one I can purchase to use specifically for testing the X5? Also, does anyone have the fuse diagram that shows which fuse is used for the rear air suspension that has already been deleted?

80stech · #8 12-28-2020, 08:45 PM

I'm not sure how to post a link but type in Neoteck 9999 in Amazon. That one looks pretty good, has some nice clamp type test leads and even does temperature. Way more than you need but I would say a good value. I'm sure Home Depot or Auto parts store would have something as well. You are looking for something that will measure milliamps and if it has 10 or 20 amp capability even better. It would probably be best if you measured and verified the draw at the battery before you go to individual circuits though. Maybe some of the guys who have a battery switch installed could chime in with what they get for measurements since the battery switch makes it super easy and we would have a good reference point.

Purplecty · #9 12-28-2020, 08:54 PM

Quote:

Originally Posted by 80stech

I'm not sure how to post a link but type in Neoteck 9999 in Amazon. That one looks pretty good, has some nice clamp type test leads and even does temperature. Way more than you need but I would say a good value. I'm sure Home Depot or Auto parts store would have something as well. You are looking for something that will measure milliamps and if it has 10 or 20 amp capability even better. It would probably be best if you measured and verified the draw at the battery before you go to individual circuits though. Maybe some of the guys who have a battery switch installed could chime in with what they get for measurements since the battery switch makes it super easy and we would have a good reference point.

Yeah definitely plan to test for a draw first. Stepehen mentioned if it has 25-50 milliamps when the car is asleep, then it definitely is drawing too much power and will require testing each circuit individually until the draw is in an acceptable range. Is this the multimeter you are referring to?

https://www.amazon.com/dp/B08B3DZVZM..._DaO6FbZ7PCHPC

80stech · #10 12-28-2020, 09:32 PM

Yep that is the one that I would get. That's a lot of meter for the money. The weak spot will be the quality of the test leads, they will oxidize after a while and give poor readings if you don't keep them clean but good test leads are worth more than that by themselves.