Need help, car completely dead
 

I have a 2001 E53 4.4 that I let sit around for about 2 months, the running lights were left on. I didn't get a chance to look at it until this past week, I had the driver's door open so I was able to pop the hood. Typically I can put my portable jumper pack on it to start the car. This time it did not work, I put a 10 amp charger on it overnight, and nothing. Even with a charger attached to the front hood terminals I do not get any power inside, no interior lights or any kind of power. Does anyone know what may be wrong, is there a main fuse that may have blown? Thank you in advance.

Gregy

Update, looks like some of my chargers were just not powerful enough send power to the car in "supply mode". I dug up my old Noco charger and it was able to give power to the car, the battery is in bad shape but at least I can get to it to replace it now.

Two months on constant draw will drain a battery good. It's toast.

I keep a booster battery pack in the X5. I'm so afraid an amp draw will start at any time. It's been over a year since replacing the GMIII module on mine. Even after 3-4 weeks, it starts right up. The 11 mA draw is real on mine.

[emoji95]These cars don't like to sit...they are made for driving and hwy driving, from my experience.[emoji106]

I always try to maintain my batteries, especially when the vehicle sits
 

At the current time, my '01 X5 3.0i has been undriven/unstarted for 2 months (and my '04 Chevy 2500HD 3/1 months since last driven/started...same for the '98GMC); I need to check the electrolyte levels on each, since this summer has been so hot, and I haven't checked since May. Nevertheless, I still trust that each will start, since I keep all my vehicles on low amperage battery charger/maintainers (except for the HHR Panel that my wife drives nearly everyday...and never remembers to unhook the charger/maintainers).

see this post:

https://xoutpost.com/1216543-post7.html

I haven't yet had any problems with a dying or "dead" battery during the 8+ years I've been using charger/maintainers (trickle) on my vehicles, but if I do, I have a proven method to bring them back to life, using my Schumacher XCS15 charger (2-10-15 amps), that I initially bought to use on my camping trailer battery (an Optima Yellowtop AGM), but I've used it on everything since 2013...it has even resurrected two "dead" AGM batteries for me, and charged up several "dead" regular batteries over the last 10 years. It also automatically switches to a lower charge rate, which I use to bring up batteries overnight, un-monitored; a feature I haven't had on more expensive chargers, from the old days. I've expected the solid-state circuitry to fail (they're not as long-lasting as old-school chargers), but it has been perfect, so far. I haven't even used my garage-type charger (10-20-40-200 amps) in several years, since I have had the XCS15 (and no longer need to take the big charger to drag races).

Like the OP, I can put my portable jumper pack on it to start the car, if away from home (I also have a 9v battery, with jumper wires to connect to the battery posts underhood, in case the remote fobs or main battery fail to open the locked door/hood) hidden underneath the X5 in a sealed container.

I carry the small AstroAI Car Jump Starter along in a bag whenever I drive the X5, or take another vehicle on an out-of-town trip, plus it contains my Foxwell NT510 Elite (my other scan tool stays in the X5 trunk), a spare cellphone/dashcam, extra charging cables for phones, etc., and some EDC-specific gear.

I was in the old-school Boy Scouts back in the early 60's, and learned to "be prepared". Maybe overdone in some cases (i.e. when camping, dragracing, just about anything....)