AWD went out!

[ColoSVXer]

I noticed with the roads being icy, my AWD is not working. Does not make any strange noises or binding, just the front wheels spin and not the rear. Prior to icy roads, transmission shifts smoothly and now where there the roads are clean. Only thing I can think of is I had a flat a few weeks ago and ran on the spare for about 30 miles. This is really frustrating as last winter during our many blizzards, my SVX was one of the very few cars on the road. I know the AWD was working very recently because during emission testing, I could see both front and rear spinning. HELP!

[ColoSVXer]

Is there any relationship with the ABS and AWD? To add to my first question; the brake light on the dash comes on whenever I brake and all the lights illuminate. None are out.

[SVX_MY_BABY]

Don't know about the abs & awd, but have you checked the fuse which enables 2 wheel drive?

[ColoSVXer]

I will check to see if a fuse is inserted today, but I doubt it because I do most of the on my SVX. I was wondering also if it might be because I have a different brand tires (same size) on the front and rear and have read the size must be => 3/32". Still, it runs great, shifts great and no noise, except the rear wheel bearings are started to get a bit noisy. Since its a 1996 and does not have the "Power" light, I read to see if the AT Temp light flashes when first starting and it does not. Even tried to see if I would get any codes per BudFreaks instructions. Nothing.

[Sean486]

Might need to replace the Solenoid C in the tail shaft of the trans .

[fasteract7]

Wouldn't the Power light or in this case the "A/T temp light" flash a code if the solenoid was defective. Why doesn't either light flash if the AWD is out ? If the 2wd fuse is empty and the 4WD slot/fuse is good, where could the problem be...? Wierd. I know it's a pain but have you tried putting all 4 wheels up and seeing if the rears spin?

[svxcess]

There should NOT be a fuse in the FWD slot during normal
operation. Putting a spare fuse in puts it into FWD mode.

[oab_au]

Sean is right, it has a problem with the C solenoid/transfer valve assemble.
If the C solenoid has a problem it will post a code, but if the transfer valve is sticking or a bleed hole is blocked there is no rear drive, and no code posted.
The rear wheels will turn when is is up on a lift as the clutch is dragging, but will slip when loaded.

This is the C solenoid/transfer valve assemble,
http://www.subaru-svx.net/photos/files/oab_au/32474.jpg

and the hydraulic circuit.
http://www.subaru-svx.net/photos/files/oab_au/34536.jpg

You can pull he tail section off, and either fit a new assemble or clean the valve and back plate.

[ColoSVXer]

oab_au, you are correct.
I had a flat on the left rear, and i could turn the wheel. Is this a major fix? I am no expert with cars, but am pretty handy. If this involves pulling the tranny, that will be beyond my scope. If its just pulling the transfer case, which I understand is mounted to the rear of the tranny, I could probably do it....I think. I ask my subie mechanic for the worst case scenario, and this includes the clutch bands being shot, he said around $1400.
Thanks for your help!

[ColoSVXer]

oub_au;

When you posted;
"If the C solenoid has a problem it will post a code, but if the transfer valve is sticking or a bleed hole is blocked there is no rear drive, and no code posted."

If a bleed hole is blocked or transfer valve is stuck, this this still involve removing the transfer case?
Thanks for your help!

[oab_au]

Originally Posted by ColoSVXer

oub_au;

When you posted;
"If the C solenoid has a problem it will post a code, but if the transfer valve is sticking or a bleed hole is blocked there is no rear drive, and no code posted."

If a bleed hole is blocked or transfer valve is stuck, this this still involve removing the transfer case?
Thanks for your help!

Yes the C solenoid and the Transfer valve is a complete assemble, the steel plate behind this valve has the bleed holes in it.
When you remove the rear of the case there is a wire that runs between the two, slide the case back a bit and unplug the wire, so it does not break, and use a new gasket.

[ColoSVXer]

Also noticed my usual miles/gal ~ 19city/28 hwy are now ~ 12-13! Funny, it still runs extremely well, no noise, binding, grinding and no codes, just no AWD! Very frustrating to loose it here in Colorado especially this time of year.