Alarm causing a parasitic draw

[Legacy777]

Well I have had an issue for several years now that when I leave the car sit for several weeks the battery will be drained to a point it is tough to start or won't start. I'll usually just hook the charger up to it and she'll fire right up. Since I've got an Optima Yellow Top deep cycle battery, it hasn't been a big deal.

Well this past Wednesday I was going to go get gas and of course the battery was dead, so I jumped it, it fired up, and I didn't think anything about it. Usually, I'll just jump it and it'll charge up while I drive. Well when I went to restart the car after I got gas, it wouldn't start. Luckily I had jumper cables so was able to get the car running again.

When I got home and put it on the charger it said the battery was discharged to about 15-20% capacity! I was rather pissed, so I decided to try and figure out what the hell was causing the draw. I tested my Impreza to get a baseline reading of what is a "typical" draw when the car is off. It was reading 9.24 mA. I then tested the Legacy and it was reading 29.6 mA! That's a little over three times as much!

All the power is routed through the fusible link and five slow blow fuses (SBF). You can see that in these two diagrams:

http://www.surrealmirage.com/subaru/fil ... uting1.jpg
http://www.surrealmirage.com/subaru/fil ... uting2.jpg

To figure out where the draw was coming from I pulled each one at a time to see when the amperage dropped. It wasn't until I got to SBF-4 that I saw the amperage drop. As soon as I pulled it, the amperage dropped to 7.35 mA. I pulled the remaining SBF and checked them all for continuity, and then put everything back in except SBF-4. The amperage draw remained at 7.35 mA. As soon as I put SBF-4 back in the amperage jumped back up.

The only thing left I need to do is verify that my alarm isn't the cause of the draw....I am pretty sure it's not, but need to check it. I'll disconnect the B63 connector to see if the amperage drops, and if it does, then I feel pretty damn confident it's the ignition switch.

In which case, it looks like I'll be getting a new ignition switch. From what I can tell in the parts book and from reading on here, it can be replaced without messing with the lock cylinder. The part # is 83131GA060, and can be had for $40 at Subarugenuineparts.

Anyway, hope this helps anyone that may have similar issues. I hope this is the problem and a new ignition switch fixes it. It's becoming VERY annoying!! I'll be taking pics as usual.

If anyone has replaced their ignition switch and has any comments or tips, that would be appreciated.

Thanks

Edit: Did some additional testing and it looks like the alarm brain is the cause of the draw. Updated post here.

[oldscoobyturbo]

yes you can replace the ignition switch without changing the key cylinder

[FundamentalyConfused]

Yes you can change the switch without changing the lock cylinder.

You will however have a TON of fun getting out those snapped off bolts that hold the switch to the column. My suggestion is, if you have easy out drill bits, is to drill a small hole and use the easy out. My Haynes manual says to use a punch and hammer to get them out, that was too much fun getting my replacement at the junk yard.

When you measured the amps did you just take the reading off the battery terminals?

[Legacy777]

I was afraid there was going to be some issue about the bolts....haha. Are they special bolts or just the fact they get stuck?

Yes I just measured the amps at the battery terminal. You need a decent meter that will read the amps and you put the meter in between the battery cable and the post.

[oldscoobyturbo]

the electronic part comes off without removing bolts. the key cylinder needs the bolts

[evolutionmovement]

Yes, as Diesel Devil said. When I went from one GL to another, I stupidly had the old key still on my chain. Tried to start the car with it and it went as far as turning the coil on, but wouldn't engage the starter (I wrote this into my first book, but as the character stealing the car) and when it came out, the lock was ruined. Replacing the lock mechanism with the one from my old GL was a PITA because of the security bolts, but the electrical portion, which only has a slot so it can be turned with a screwdriver or similar, uncsrewed normally. I ended up relocating it to the dash using the lock part from my old car and leaving the original, dead one as a red herring for thieves looking to get their hands on the coveted 1983 Subaru GL sedan.

Also, IIRC, you have an upgraded alternator, but using it to recharge the battery that often will likely reduce its lifespan. It's really meant to just top it off and maintain it.

[FundamentalyConfused]

The heads of the bolts were designed to snap off when they installed them so there's just an inverted cone shape left that's recessed in the hole.

When I was trying to get them out I had thought if I could cut a slot so I could use a flat-head screwdriver this would be simple.

Once they get loose it does get easier to remove but I had troubles getting one bolt to unstick.

[FundamentalyConfused]

Here's a couple pages out of my Haynes manual. I can email them too if you need to read them better.





When I took the spare one off that 1995 legacy I just took the whole thing off the steering column. At that time I wasn't sure if it could be separated or interchangeable or not so I just took the whole thing.

[Legacy777]

Also, IIRC, you have an upgraded alternator, but using it to recharge the battery that often will likely reduce its lifespan. It's really meant to just top it off and maintain it.

Yeah....I usually try and charge the battery via the battery charger, vs. the alternator....I really don't drive the car much.

[Legacy777]

Thanks for the comments everyone!


FundamentalyConfused, I've got the Haynes manual so I'll check out those pages.

Thanks!

[91Beater]

It's a mechanic switch, so I really can't understand how it would affect parasitic draw, but let me know if it fixes the issue. I'd like to see what was, if there was anything wrong with the old switch.

Though its not a fix, you could add a always-on 12v socket like I did, and to it, install a 2-way splitter and dedicate one to a solar charger. That should be enough to offset the drain.

[Legacy777]

I agree, I'm not sure how the switch can be bad....so I need to do a little more probing around.

I'll let you know what I find.

Thanks

[Legacy777]

Well I may have been a little hasty with the ignition switch. I did some more testing this evening, and I believe the problem is related to the alarm. I unplugged & plugged the alarm in and heard a relay clicking inside of the brain. I did that a couple times, and even with it just plugged in it would seem to click on and off for a bit. Then the alarm LED stayed lit.

When I had the meter on, it would peg/overload the milli amp setting, so it's definitely drawing some current. I'm pretty sure with the way it's wired up I can drive the car, I just won't have an alarm. I need to look at the wiring diagram for the alarm and maybe see if there is a repair center I can send it to.

Without the alarm plugged in, the amperage draw settled at 7.32 mA. So that seems plenty normal. The alarm claims that the largest draw of current is from the blinking LED light....so I'm pretty sure something isn't right in the alarm's brain. Which sucks

[91Beater]

30mA isn't out of line. If you don't drive the car much, hard wire a always on 12v outlet and use a battery tenderer or if it's not garaged, use a solar maintainer

http://www.harborfreight.com/15-watt-so ... 68692.html

[Alphius]

I know most alarms with ignition cut have the relay wired NC, which means that with the alarm armed it will draw enough power to keep your relay tripped to prevent someone from starting the car. A standard Bosch automotive relay takes a continuous draw of around 20mA to hold the contacts closed.

30mA draw on a 100% charged Group 35 YellowTop should cause a no-start after about 33-34 days of sitting. Any shorter, it should still start. Any longer, you are most likely dead in the water. If you are getting significantly less than 33 days of sitting time, I think your battery is no longer operating at original capacity.

Sounds to me like your alarm is working as intended and your battery is getting marginal.

[Legacy777]

So the plot thickens....

The way the starter interupt relay is setup is that it will only be energized (ie not be able to start the car) when the ignition is ON. When the ignition is off, the relay is not engaged and does not draw any current.

The main point is that, I used to not have a problem....but now I do....and as any good troubleshooter knows, you look at what has changed. The reason I said the plot thickens is because the few months I've noticed that the electrical door locks have been actuating very slowly/weakly. When I pulled the alarm brain out, they're back to normal and work at expected speed.

So I contend that I've either got a wiring issue or something internal to the alarm. Honestly, I'm kind of leaning towards wiring, because I do not have a door actuator setup for my alarm, so the only common denominator between the alarm brain causing the door locks to actuate slowly is possibly a common 12v or ground point that the alarm installer used.

Plus, I had found a couple years ago that the alarm installer did NOT install the starter interupt relay correctly. One day I was messing around with the alarm and decided to sit in the car arm the alarm and try to start the car. To my surprise, the car started! The relay was not wired up correctly, so I certainly wouldn't put it past the fact that something isn't right with the wiring.

[vrg3]

Not that this is gonna help you, but for completeness' sake -- Like 91Beater says, 30 milliamps isn't a big deal. The usual rule of thumb is that anything less than 40 mA is fine.

The fact that you heard clicking when you plugged/unplugged the alarm makes me think something's getting constant power when it should be getting ignition-switched power.

You're probably right about the lock actuators -- they're slow because the alarm is drawing current through a shared circuit.

Would you feel comfortable posting the make/model of the alarm? We could look at the install diagrams and figure out what you need to check.

[Alphius]

Regardless of any alarm inconsistencies (and your alarm install does sound a little messed up) you are still drawing only 30mA with the car sitting, right?

Like I said before, I did the math on that and a Group 35 YellowTop Optima will have enough charge to start your car for about 33 days. If you are sure that your draw is only 30mA and you get less than that, your battery is degraded.

As far as clicking when plugged in, does your alarm flash the parking lights via an onboard relay? Mine does, and it flashes them when it first is plugged in or gets power, causing the unit to click a few times as the internal relays switch over.

Slow door locks: If the alarm is only drawing 30mA, it shouldn't affect the door locks at all even if it is on a shared circuit.

[Legacy777]

For now the alarm is out, and I'm going to wait until I pull the dash to do some more troubleshooting as I don't feel like crawling on my back to look under the dash.

Here's the wiring diagram.
http://main.experiencetherave.com/techi ... wiring.pdf

Not all the outputs are hooked up. I don't have the ignition immobilizer relay, nor do I have a trunk or door lock actuator.

Just checked and if I remembered to pull the little dots out correctly it was new in 2007. I thought it was newer, but guess not. It probably wouldn't be a bad idea to have the alternator tested too. I'll see if I continue to have issues or not now that the alarm is out. The only other thing I noted that after recently charging the optima with Optima's own charger and the car sitting for a couple days (week or so) when I did a battery check using the charger, it said it was down to 75%. I'm not sure if that means anything, but that's what the charger said. I'm not sure what the battery voltage was.

I'm kind of waiting until I start the 6spd swap and pull the dash to really dig into it, but I appreciate the feedback.

[FundamentalyConfused]

How old is the battery? They usually start losing charge after 5 years.

[91Beater]

Battery life greatly varies on use.
Temperature and abuse are big factors.
Deep discharge over a long period is considered an abuse.
Even if it's deep cycle, the stipulation is that you need to charge it back promptly. If you often let it discharge to 25% left over weeks, it degrades them.

[Legacy777]

How old is the battery? They usually start losing charge after 5 years.

Just checked and if I remembered to pull the little dots out correctly it was new in 2007.

[Legacy777]

Just a quick update on this thread. I did a little testing tonight and with the alarm brain out of the car and just the 12v power & ground wired up to the brain. It showed 18.67 mA both armed & disarmed. It jumped to 44.6 mA for 30 secs after disarming to hold the dome light on.

Adding the 18.67 mA & 7.35 mA from when I pulled the alarm brain is 26.02, it's pretty close to the original "resting" amperage I tested of 29.6 mA. The only difference is when doing the testing tonight I did not hear the internal relays clicking on and off randomly like I did before, so I'm suspect of the wiring. I'll check all the wiring out when I yank the dash to do the electronic speedo gauge cluster.