100 milliamp draw with alternator disconnected, all fuses and relays pulled?

[idosubaru]

disconnected alternator post and connector

all the fuses in the cabin fuse box are pulled

all the fuses in the engine fuse box are pulled

all the relays in the engine fuse box are pulled

 

what else is connected to the power circuit?

 

where do the engine/trans/VDC controllers pull power from? 

 

is that a bad battery?

it's 2 years old. 

 

can i test the battery for a draw? 

battery starts and works fine. 

 

if i simply put the amperage leads on the positive and negative terminals of the battery will that tell me if the battery has an internal draw - or would that short it out?

[idosubaru]

2002 OBW H6 VDC

[Fairtax4me]

if i simply put the amperage leads on the positive and negative terminals of the battery will that tell me if the battery has an internal draw - or would that short it out?

Don't do that, you'll blow up your meter. If you're lucky it will just blow the fuse, but depending on your meter it can be hard to find fuses and they're often much more expensive than a regular blade fuse.

 

How is your meter connected?

 

Have you allowed time for all of the control modules to power down and go to "sleep" mode?

 

When you say you've pulled All of the fuses, does that include all of the slow blow fuses? (Theyre usually red and green in the older cars, not sure about the 02) What about the main fuse or fusible link?

Edited January 23, 2016 by Fairtax4me

[idosubaru]

THanks, i wont' short the battery.  Meter is in-line between the negative battery post and the removed negative cable.

 

I rest the negative cable on the terminal with the mutlimeter probe attached then lift it off - probably 30 seconds, it seems to settle down - does that sound long enough?

 

Ah - crack - yeah the slow blow fuses are the "bolt" down fuses in the main fuse box?

I didn't remove those yet - I guess it's one of those circuits - what are those typically for - if there's a simple way to delineate that?

[idosubaru]

I'll go test those slow blow fuses shortly. 

 

While we're talking about testing - why can't you test the draw by pulling a fuse - and then insert your multimeter in place of the fuse terminals to test the draw on that one circuit?

 

Everything I read says to go between the battery post and cable. 

[porcupine73]

Hm does that include the main fuse? One thing I can think of off hand that has no fuse of course is the cable to the starter. The meter in series with one of the battery terminal connections will just show the current flowing between the battery + and - terminals (it wouldn't show any internal leakage inside the battery itself).

[idosubaru]

No it doesn't include the main fuse or a few (4 or 5) of the big box slow-blow fuses fairtax talked about, they are bolted down into the fuse box. 

[Fairtax4me]

Most of them are like the "main fuse" for a handful of circuits. After going through the SBF the path is broken up to maybe 5-6 fuses. Others provide direct power to control modules and related components or the ignition switch.

 

You may not be getting to control modules into Sleep mode with the method you're using. You really need to be able to cycle the key On for 15-20 seconds, then turn off and remove it from the ignition switch.

Cut a section of wire about 18" long and strip about 3-4" of insulation off each end. Wrap one end around the negative battery post and the other around the negative cable terminal. (Aligator clips can also be useful here)

Connect the terminal to the post and cycle the key On wait a few seconds then turn it off. Remove the key from the ignition. Make sure all dome lights are off, all doors are closed.

Carefully remove the negative cable from the battery making sure not to disconnect the wire. If the wire gets disconnected you'll have to start over.

Now clip your meter leads to the negative cable terminal and to the battery post. Then you can disconnect the wire from the battery and cable.

Now wait another 10 minutes up to maybe an hour to make sure the control modules all go to sleep. It should only take about 10 minutes on a Subaru.

If you watch closely you should be able to see the amp reading drop a few times as the various modules power down.

Wait maybe an hour to be sure then see what the meter shows.

Edited January 24, 2016 by Fairtax4me

[idosubaru]

thanks fairtax it was the SBF #5 - i completely forgot to pull those.   (they are not bolt down - just the main fuse is)

 

now i gotta track down what's on SBF#5

[idosubaru]

cracksmoker - i don't have any FSM's on my new laptop. 

 

2002 OBW H6 SBF #5 circuits anyone? 

[porcupine73]

Is it any of these?

 

[idosubaru]

Rear O2 sensor looks most likely - I'm out of town and in the dark can't seem to find the connector - accessible through engine bay or underneath only?

Edited January 24, 2016 by grossgary

[idosubaru]

*edit* rear O2 sensor most likely...

[idosubaru]

Is it any of these?

2002 fuses.png

 

No, it's SBF #5 - which is one of the blank/unlisted boxes between Fuse 4 and 5 in your diagram. 

[idosubaru]

this is an impreza but it looks very similar to this layout, with SBF5 in the outback looking similar in location/layout:

 

https://www.google.com/imgres?imgurl=http://i345.photobucket.com/albums/p367/asoka05/742dcb2e.jpg&imgrefurl=http://forums.nasioc.com/forums/showthread.php?t%3D2233831&h=764&w=1024&tbnid=dDpr-IOI071O9M:&docid=DHFYe2SlS8J6bM&ei=4iCkVurrO-yujgT436O4BA&tbm=isch&ved=0ahUKEwjq5L22nsHKAhVsl4MKHfjvCEcQMwhOKCowKg

 

see how the SBF fuses aren't labelled in your diagram?  it only lists the blade type fuses. 

[porcupine73]

Ah a mystery fuse maybe someone snuck in a datalogger. This one looks interesting at least for showing the relays and such but doesn't unfortunately have this particular sbf5 info. On some it seemed to indicate SBF5 goes to the power windows and sunroof but not sure if that applies to this particular model+year.

 

[idosubaru]

It's not the rear O2 sensor.  Still searching for circuits powered by SBF #5.  Might have to wait til I get home, I'll just leave it unplugged overnight. 

[john in KY]

Why not just pull it and note what now doesn't work?  

[Fairtax4me]

Closest I have is 03.

Looks like SBF 5 supplies the DLC, ECU, immobilizer module, main relay,

 

and via fuse 13 the fuel pump relay. If you already pulled 13 we can rule that out.

 

Immobilizer module should be on the right side of the steering column.

12 pin opaque connector.

 

Is anything plugged into the DLC? Check it and make sure there is no corrosion or crud in there.

[Cougar]

Fuse SBF 5 is the main fuse for power to the engine sensors, ecu, and to the OBD2 port, like Fairtax4me stated. If you have something plugged into that port you have found the problem. Most of the current the fuse passes can't pass until the ignition is ON and the Main Relay is turned on. If the trouble isn't on the OBD2 port then disconnect the ECU and see if the current drops down.

[idosubaru]

hmm, good to know, there's a relay for everything but the OBD port? 

could that relay create a draw?

 

i'll verify first if i even have an issue - there's some suggestion that i wasn't waiting long enough for computers to set. 

[porcupine73]

This might be a little tricky to do but maybe would work, is after the battery has been connected say overnight for everything to settle in, put one of the meter terminals on the battery terminal, and the other on the cable lug, then lift the lug off the terminal? That way nothing ever loses power and maybe you would see the true parasitic draw without anything taking extra due to powering up?

[Cougar]

The OBD2 port and the ECU tie directly to SBF-5. The relay can't cause a current draw unless the contacts are shorted together. The draw would be very significant if that was the case.