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Scooby Fan 10-24-2012 12:37 PM

Battery issues
Yup....yet another battery problem thread, but before you start flaming me....I did search and read all that I could find...just nothing quite specific enough.

The situation....2006 LGT sedan with 58,000 Km...totally stock....only electrical after market accessory is a Garmin GPS running off the cigar lighter(Disconnecting it does not affect the problem) New 550 CCA battery installed a few months ago....all terminals are clean and secure. Battery will go to DEAD in about 4-5 days if not driven.

The car has been to the dealer about this numerous times while it was still on solution.

Battery readings across the terminals
Running at idle...............14.4V
Running at 2500 rpm........14.4 V
After shut off.................12.7 V
After off 1 hr..................12.4 V
After off 5 hrs................12.2 V
After cold overnight........12.1 V
After start and 2 km drive...12.6 V

I did the Dark Current test as outlined in TSB 07-62-07
Milli amp draw down fluctuates between 1 mA and 18 mA...never higher and no where near the suggested max of 150 mA

Love to hear from anyone on here with any serious ideas about his problem.

compsurge 10-24-2012 12:54 PM

Start pulling fuses to see which one reacts? Is there an alarm system installed?

06silvarubiLGT 10-24-2012 12:58 PM

^^this.. At this point I think you should continue to check voltages over a longer period of time. especially since you know it takes it 4-5 days. Have you followed the ground wire down to frame/or wherever it may go, they do fray sometimes?

Max Capacity 10-24-2012 01:13 PM

Have you PM'ed members like Frank_ster, m sprank, BAC5.2

I'm sure one of them could be some help.

compsurge 10-24-2012 02:31 PM

Also, have you unplugged your battery to see if it discharges over time by itself (just what I'd do)?

Spec B 10-24-2012 02:54 PM

I have not taken measurments but I have the same issue (car has 40k miles) i just ordered my 2nd optima yellow top battery. My current battery (2 years old) will not hold a charge at got progressively worse over time. I also bought a battery tender in the hopes of saving my current battery but it will not charge it at all. :(

compsurge 10-24-2012 02:58 PM

Have you tried a more generic battery from the auto parts store? It could be as simple as not driving enough to keep the battery in good shape. The average lead acid battery needs to be charged within 30-60 days of sitting idle at standard room temperature to retain its life.

Scooby Fan 10-24-2012 03:30 PM

Thanks for the replies.
All the connections are solid and fraying
The battery does not drain down when not connected to the car
No alarm on the car...just the OEM immobilizer
The draw down measurement is so low I can't see where pulling fuses will tell me anything.
This is the second battery in the car and it reacts exactly like the original.
You can tell from the ultra low mileage (Barely 35,000 miles in 7 years)that the car does not get a lot of driving...a lot of short trips with occasional holiday drives...but... I do drive it almost everyday.
I am going to leave it for a few days in the garage to see what the voltage drops to.

AkumaMax 10-24-2012 04:20 PM

There has to be a short somewhere. A nicked wire or even a bad connection. I would check out the alternator as well. If you say the battery is good disconnected over time then there is only one other major part that coincides with the battery.

Scooby Fan 10-24-2012 04:55 PM

Good plan...>I will check that tomorrow.........I suppose it is not impossible that the juice is bleeding back through the alternator, but I think that would show in the "Dark Current" test for amp leakage,,,,as you can see my readings for that are very low compared to recommended specs.

Obviously, what I am hoping for is someone who has had the same sort of problem and readings and has found the solution. I hope it is as simple as driving it more........or maybe driving it to the dealership for a new Subaru ;)

OBieXT 10-25-2012 01:29 PM

Are you leaving the key in the ignition? Just putting the key in the ignition (even without turning it on) seems to wake up the anti-theft system and it apparently starts polling the chip in the key. This puts a load of about 3/4 amp on the battery. Although this is a small load, over time it is more than enough to run the battery down in a 3-4 day period. Its possible that the contact that senses when the key has been inserted occasionally sticks thus leading to a dead battery.

Scooby Fan 10-25-2012 01:36 PM

No....the key is always out and obviously during the test as prescribed in the Subaru service bulletin....Not sure why, but the bulletin requires that the doors be locked too......Probably to arm the security system, but I don't have an alarm. I tested it with the doors locked and unlocked...same results exactly.
BTW....checked the problems there.
It is hard to find a leak when the test shows there is no draw more than fact the Subaru test shows that my car draws down way lower numbers than normal....The quest continues;)

compsurge 10-25-2012 02:18 PM

Are you the original owner?

Check the trunk for signs of a tow package or something.

LGT612 10-25-2012 02:50 PM

The time consuming way to find a parasitic draw is to hook up an ammeter to the battery, negative side cable, and start pulling fuses and see if the reading fluctuates.

700watts 10-25-2012 02:55 PM


Originally Posted by LGT612 (Post 4130557)
The time consuming way to find a parasitic draw is to hook up an ammeter to the battery, negative side cable, and start pulling fuses and see if the reading fluctuates.

That is your only choice...or you'll be chasing your tail

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