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The Beast eats batteries for breakfast!

1582 Views 6 Replies 4 Participants Last post by  Eman99
Hey guys,

I'm kinda stuck with a one year old problem that's eating batteries like cookies. I kept having problems starting the car after parking it 8-10 hours which let to numerous dealer and self troubleshoots, new batteries, new fan relays, current drain tests etc...

Long story short, I just purchased a new battery since the old one was nuked due to several discharges.

- New battery's voltage at the shop was 12.62v and the 'eye' was green.
- New battery with the car turned on shows 14.2 - 14.6v thus alternator/charing system should be OK.
- New Battery voltage after a 10-15min drive is 12.6v (12.72 sometimes, 12.8v)
- I Hooked up an meter in series and checked the drain which was at around 3A then after 15 minutes it was 0.02A both with the alarm on and with the alarm off. I glanced at it several times over the course of 2-3 hours and it seemed to stay around the 0.02-0.03A range.
- Sometimes while the car is parked armed, the alarm still randomly goes off.
- After parking 8-10 hours, the battery shows around 12.5v, slightly lower than a full charge.

All this leads me to believe there's an intermittent problem that wakes the car *sometimes* and that's slowly eating the battery. In case the drive wasn't long enough to full charge the battery, the battery can drain during the time that it's sitting parked. After a couple discharges the battery is as good as dead.

My hope is to not drain this brand new batt. Any troubleshooting suggestions? I'm thinking pulling 1 fuse per night and seeing if in the AM there's a lower voltage than in the evening. Can you suggest which fuses are the common culprits that I should start with?
1 - 2 of 2 Posts

· Registered
7 Posts
This has only ocurred to someone I know that was a "person of interest" in the eyes of the law.
Police place bugging, tracking and monitoring devices in the vehicle that often drain batteries.
Only you or a PO might know if this is a possibility.

Otherwise I have no other idea

· Registered
7 Posts
It can be intermittent.
Remote activation.
GPS input for activation.
Voice activation.
Stationary activation.
Timed activation.
Random activation.

Don't ask me how I know.
Have you had any indicator bulbs fail?
1 - 2 of 2 Posts
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