Auto shoulder belt difficulty

Our '94 Legacy has automatic shoulder belts. When they operate properly, they slide forward when the ignition key is off and the door is open and slide back when the door is closed and the ignition key is on. Beginning a month or so ago, the driver's side belt began to hesitate in both the open and closed position. Now, it rarely moves, staying, fortunately, in the closed position. My Haynes manual does not discuss this feature nor is it included in the wiring diagram. Here's what I need to know: the components in this system, their location, and at least a basic circuit diagram or description.

Phil

Reply to
Phil Andrus
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I had a non-functioning, automatic, passenger side shoulder belt in my '89 XT-6 when I bought it. Turned out to be a poor harness connection. In diagnosing the problem, I started first with the dissected Legacy's down at the local u-pull it yard to see how Mr. Subaru had designed his shoulder belt system... Apparently, in the Legacy cars I inspected (no XT's to be found in the yards in my area), there is a seat belt control computer in the trunk area of the sedan, or back behind the driver's rear strut-mound, whatever you call it bump in the cargo area of your wagon variety. The harnesses from the auto seat belt assembly end up there. In my XT-6 however, turns out the control unit was housed in the side of the car, right behind the passenger door, behind the molding with the passenger armrest under the non-moving side window.

Never finished diagramming the whole layout for the auto shoulder belt as I had success before I needed to, but from what I recall, there is a switch to tell the system when the latch reaches the front position, one to tell the system it has reached the rear position, circuitry to tell the computer whether the belt is plugged in or not, and electrical for the motor. This stuff all runs to a control unit, housed in a gray metal box slightly larger than the diameter of a 3 x 5 card, and an inch or so thick. One end has a large, white, 17 pin harness connector while the opposite end has a white, 7 pin harness connector. The box has a sticker on the top that says, "P/B CONTROL UNIT" a Subie swish logo, "88013AA041" "152000-0341" "12V" "DENSO" "MADE IN JAPAN". I apologize but I can't remember anymore the exact year Legacy this unit came out of, but I do remember it was early ninties, so should be similar to what you have.

I was able to determine that the seat belt motor was fine by undoing it's harness and hooking a 9V battery directly to it. Polarity one way, then the other, and sure enough, the dead belt latch went and came, so it wasn't the motor.

Anyway, to short cut a story that spans an afternoon tracking down all connections involved, verifying each connector is clean and harnesses firmly plugged back into place, haven't had a problem since.

Seems a fair amount of circuitry just to control the forward or back travel of the mechanism. Course, it's nice the seat belts don't zip forward when the door sensor thinks the door is open and the car is driving down the road, so maybe that has something to do with it! (-;

Good luck with your hunt.

~Brian

Reply to
strchild

Hi Phil!

On Wed, 14 Feb 2007 18:58:23 -0800, Phil Andrus wrote:

Alas, an all-too-common problem with these cars. I can probably provide you with that section of the manual, but I can offer reasonable assurance that it is the mechanism it's self that has failed. (I've replaced way too many . . .) Best solution, assuming that the latch is all of the way in the back position (seat belt light is off), is to simply unplug the damned thing, and work the shoulder belt manually. Connector is behind the lower B-pillar cover. For easier access, remove the drivers seat. You will also need to remove the door sill plastic on both doors. From there, just grab the trim piece near the top and pull it off. This seems a bit unlikely at first, but once started it'll come easily. IIRC, there is a way to manually operate the drive gears once the cover is off; you might be able to use that to move the latch all of the way back if it isn't already there. Once unplugged, the seat belt light will stay off, and the warning chime will be blissfully silent. If you decide that you must have the automatic seat belt, you will need to replace the entire thing. Pull the lower B-pillar cover as described. Pull the upper part as well (push-in clips, and maybe a screw or two), loosen that side of the headliner (more clips, be careful or you'll crease it), and remove the A-pillar plastic (again, hidden clips). Remove the 6mm screws holding the track at front and along the top, and the larger hardware at the rear. Replace and reassemble. Hint: remove any clips that remain in the sheetmetal and replace on the plastic before installing. A salvage yard will probably charge $75-$100 for one of these. I don't even want to guess what Subaru want's for one, but I'll bet it's a significant percentage of the value of the car . . . :-P Hope this is helpful.

ByeBye! S.

Steve Jernigan KG0MB Laboratory Manager Microelectronics Research University of Colorado (719) 262-3101

Reply to
S

Had a look at mine last night. In all likelihood, you will also need to remove the grille to access the headlight assembly (not for adjustment; only to remove). It's held on by way of two or three kinda funny clips, and possibly a screw. To release the clips, reach in with a small standard screwdriver and depress the little lever (use a flashlight; you'll see what I'm talking about) while pulling outward gently. Stuff a piece of cardboard or whatever comes to hand in behind the clip once you loosen it, or it will snap back in when you move to the next one.

Bye! S.

Steve Jernigan KG0MB Laboratory Manager Microelectronics Research University of Colorado (719) 262-3101

Reply to
S

Steve-- wrong post.....

Reply to
nobody >

Sure 'nuff.

"Measure twice, cut once . . ."

Thanx!

ByeBye! S.

Steve Jernigan KG0MB Laboratory Manager Microelectronics Research University of Colorado (719) 262-3101

Reply to
S

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