Can't locate ABS brain to swap out

[kahoona360]

Hi

 I have a problem with my ABS system which my mechanic says is probably in the Brain because there is no response when checking for an error code. I have an 1097 Suba Ourback legacy 2.5 auto. I got a used one to replace it but I cannot find it to replace it anywhere. I looked for it here with the search with no sucess and I tried Google in general. I kave looked under the dash on the drivers side, under the rear seat, under the passender seat and  under the hood ahead of the passenger side wheel.I did pull up the carpet beneath the reae seat  but no other carpet. There are many buts and pieces of the system but nothing that looks like what I have as a replacement. Can anyone tell me where to look please? Tere is a picture of the replacement part I got just for reference. It has a very large socket for a wire harness plug so I have been looking for anything else with that kind of huge wireing connector too. No lucj so far.! I tow a boat and I really need that ABS.

Thanks

Rob

[86BRATMAN]

If I'm not mistaken its located on/beside the abs unit under the hood.

[Fairtax4me]

Edit: FSM says ABS control unit is under the dash passenger side to the right of the glove box.

 

But since we're on the topic. Checking ABS codes is actually very easy, and its possible your mechanic doesn't know the procedure or is using a code scanner which is not capable of reading Subaru ABS codes. I know there are some aftermarket scanners out there that read Ford GM and Chrysler codes, but not many for Japanese or European cars, at least not on the US market.

 

Under the dash on the drivers side to the right of the steering column you'll find a small black 6pin plug(kinda has a U shape with the pins), and two small black wires with pins on the ends taped to the wire harness.

Looking at the plug with the lock tab pointing up, stick one of the black wire pins into the lower right socket.

Turn the ignition switch to ON, and the ABS computer will be in diagnostic mode. The ABS light in the instrument cluster will start to blink any stored codes.

The first blinks will be a code 11, (blink, pause, blink) to indicate diagnostic mode. Any stored codes will be blinked out after that. When the light blinks code 11 again that is the end of stored codes. The code blinking will repeat for about 5 minutes, or until you turn the key off.

 

Count the blinks and post what codes you get here and I or someone else can look them up and let you know what they mean and what to do to fix them.

 

Usually ABS light is on because of a dirty tone ring or wheel speed sensor, or damaged wiring to one of the wheel speed sensors. Occasionally the G sensor under the center console will go bad because someone spilled a drink on the console.

Edited July 3, 2013 by Fairtax4me

[idosubaru]

what he said - were the codes read via the wires/pins under the steering column on the drivers side?  those will flash the codes.

also make sure the ABS light works so that it can blink the code.

[kahoona360]

ALRIGHT! Perhaps there is hope. I am familiat with the tangled jungle of wires beneath the dash on the drivers side. I just finally got everything to stay up there using six zip ties and then bed rest untill my back worked again.  I'll  try to get up there tomorrow. I read about that earlier but did not try it because the mechanic said no response. Yes he probably just tried his regular reader and then ran away.  When you say ABS Light do you nean the one on the dash that indicates a fault?   That one works. I'll definetly do that before I take a try at locating the brain again but I will try the passenger side under the dash later. I may have to buy the manual but I have often found that it does not have what I need anyway.

Thanks

[Fairtax4me]

http://www.main.experiencetherave.com/subaru_manual_scans/

Check there for downloadable manuals. The one for 97 is missing a few things, But has all of the wire diagrams, troubleshooting and diagnostic codes.

The section for the SOHC engine is missing, but you have the DOHC a way so it shouldn't matter much to you.

[heartless]

I dont remember who posted this one up some time back (whoever it was- Thanks!), but I bookmarked it then and refer to it often!

 

http://jdmfsm.info/Auto/Japan/Subaru/

 

Has manuals for many years/models of Subarus

[kahoona360]

Hi

Thanks for all the info. I am sssuming that the ABS light that flashes the codes is the one under the spedo that lights when something is wrong. I droped the lower dash and then assumed the pretzel position ( on back with shoulders in car on floor holding on by the windshield post while feet flail in air) and located the socket. The diagram in the service manuals at that link helped enpurmously and I knew from reading what you ahd done to start peeling electrical tape to look for the leads. I found them without too much trouble.  I plugged one in to position 6 and turned the ignition on at the manual indicated. The ABS light went out. No code. I assume it may have reset so I will drive it tomorrow so it comes back on and I can try it again. One thing. There are two leads. The manual only says to plug one in to position 6. It also has position 3 circled but says nothing. Should one be plugged into 3 also? Any hints will help. Tomorrow if my back still allows I can try again.

Thanks

Rob

[Fairtax4me]

I haven't read far enough to find out what terminal 3 is for, but only terminal 6 needs to be pinned to read codes.

 

That's odd that the light went out and did not blink. Even if there are no trouble codes the module should still give the code 11 to show it is in diagnostic mode.