Need to pull 96 Legacy TCU codes - help!

[guy123]

Before I go any further, let me express that I have searched this topic extensively. I have found the diagnosis connector and the ground plugs, and have the info on the "secret handshake".

 

I have a 96 Legacy L wagon automatic that is flashing 16 blinks of the AT Temp light just about every time I start the car. This started about 5 days ago while I was up in the mountains, but I am now back home to flatter ground. The only notable driveability issue is a SLIGHT shuddering when going around at a few miles per hour, like to pull into a parking spot of something. No other problems at speeds. I do notice that after coming to a stop and putting it in park, the shift change into park is a bit harder than it was just a week ago. I have checked for torque bind - tight turns over and over, varying speeds. No issues at all, everything is nice a smooth.

 

So I have tried to pull the TCU codes. I grounded out the diagnosis connector, but nothing happened upon putting the key in ON or starting the engine. So I grounded it out and tried out the "secret handshake" method detailed here:

 

http://www.ultimatesubaru.org/forum/showthread.php?t=117234&highlight=secret+handshake

 

Still no response from the light, assuming I am doing it right. I am now resetting the TCU by disconnecting the battery to see if that changes anything. Can someone tell me definitively which method of code retrieval is applicable to my model year? (grounded connector, secret handshake, both?) I am pretty confused.

 

Thanks.

[wtdash]

Hi,

Try the procedure for reading codes HERE....note there are instructions for Exisiting and Previous codes.

 

An Autozone/parts store may be able to read the codes for you - for free - too.

 

And depending on the # of miles are you due for a ATF refresh? Generally on here, @ least, it's recommended to NOT get a flush as it can makes things worse. Just drain/refill/drive 3X to get the new tranny fluid in and the old out.

 

GL,

Td

Edited January 3, 2012 by wtdash

[guy123]

Thanks for the info. I managed to find a little bit more with some extra searches with different search terms, so with all of this I I'm on the right track. I just did a couple of drain and fills a few thousand miles apart, and the ATF has never been anything but clean, light, and sweet smelling like it should be. Maybe one more drain and fill for good measure? The AT Temp light has been flashing on some start ups but not others, so maybe it isn't even a big deal... I will try to figure out what sort of driving is causing it to throw the code.

[wtdash]

Based on your symptoms, I'd lean toward either the Duty C solenoid or the rear transfer clutches/output hub.

 

The Duty C can be diagnosed by using the FWD fuse under the hood on pass. side. With the fuse in shudder should go away, which means the Duty C is working. No difference w/fuse you'll need to replace Duty C. If the shudder goes away it's a mechanical issue and you'll need to look @ R&R of the rear transfer clutches/output hub.

 

THIS POST and ThIS POST are some of the better ones on the issue.

TD

Edited January 4, 2012 by wtdash

[guy123]

Well, you just about hit it on the nose. Finally figured out the trick with pulling the codes and got a code 24 - Duty Solenoid C. This issue is so intermittent ( I started the car like 6 times or more today between work and them test driving it around after, and the AT Temp light flashed at only about 2 of the starts.) When I finally pulled the code it was a stored code, no a current code.

 

Anyway, it is now throwing the code here and there, but with very little in the way of driveability issues... yet. I'm guessing this is something that it going to get worse sooner than later? I just want to know about how soon it might do that. I might do another drain and fill of ATF, but with two done in the last few thousand miles, I don't think bad fluid is the problem. Is there anything I can do, or do I start saving my pennies for the repair? I don't have the space or time to do the replacement myself at the moment, so I want to try to wait for a convenient time to take it into a shop. Can I ride on this issue for a while, or is it anyone's guess?

 

I searched this stuff some already, but what is the usual cost of this replacement at the average shop?

 

Thanks for all the help so far!

[weldersd]

find a pick-a-part and hunt down a wrecked trans with a good extension assy. remove the old one, replace the new one, use a new gasket, you'll drain about 4 qts when you remove the trans extension do best to drain the fluid before you remove from car.

[johnceggleston]

i tink the dealer cost several years ago was 900 - 1000$. so maybe 1200$ now????

 

the labor is a little more than pulling and reinstalling the trans, time wise in a shop with a lift. first they remove the rear housing , then they replace the bad parts. not a lot of extra work with the parts, but it all adds up.

 

the parts , depending on what you actually need, will var from $200 to $500?? maybe.

 

you can drive on this for a while. but the worse it gets the more you will notice ''torque bind'' in tight turns and the trans ''relaxing'' as you shift from D to N or P. but the more it does it the more wear and tear you put on the other drive train parts.

[guy123]

Thanks for all of the info. After reading up on the subject, I'm going to go ahead and try the job myself replacing the Duty C. The car has 164,000 mi on it, and the TCU is consistently showing code 24 (Duty C solenoid) and no other codes. I swapped out the TCU with a good salvaged one just to make sure it wasn't the TCU, and it also is showing a code 24 and nothing else, so I am confident the Duty C is bad. I am getting some torque bind during some drives but not others, so I assume the solenoid is going in a out of functioning.

 

Anyway, here's the question: Can I probably get by just by just replacing the duty C, or should I get the parts to replace the duty C, the clutch pack, and the extension housing (96 housing, no steel sleeve). I want to just replace the solenoid and get out of there, the idea of messing with the clutch pack worries me a bit. But I also don't want to have to tear into it again in 5k when something else goes bad. What are peoples' thoughts??

 

Thanks again for all the great help, I will be sure to keep the board updated with my progress.

 

Also, does anyone know the part number for the extension housing? I have found the part numbers for everything else in other threads, just not the housing. Thanks.

[wtdash]

I don't see where you tried the FWD fuse. It'll tell you whether it's mechanical or electrical. Changing the Duty C won't fix your issue if it's mechanical.

 

Unless you're looking to make it like new, which is overkill, IMHO, I'd just do as suggested and get another rear housing and fix it or fix yours as noted, replace the Duty C, install a new gasket or 2 (?) and put it back together.

 

 

Or just put the FWD fuse in and drive it (if it's mechanical).

 

 

Here are all the parts you may need-double-check against your VIN:

31942AA090 Valve Ay. transfer clutch (This is the one for a majority of vehicles, some early models took a different part #.)

> > 31954AA071 (QTY=2) Gasket for solenoid and plate.

> > 31337AA120 Extension housing gasket

> > 44022AA020 Exh gasket, dual port OR 44011AC020 Single port (if needed)

> > 44022AA062 Exh gasket, large 'y' pipe OR 44011AC000 Small pipe (if needed)

> > 11126AA000 Drain plug gasket for tranny

 

GL,

TD

Edited January 14, 2012 by wtdash

[guy123]

I wanted to add that I ran the FWD fuse test on a run when I was noticing binding... the binding is equal in both AWD and FWD, so it's definitely the solenoid. I'll go ahead and order the parts and hopefully have the new duty C in by next weekend.

[guy123]

I wanted to end the thread with an update:

 

I replaced the duty C solenoid last weekend with good results. The whole job isn't difficult for someone decently-versed in mechanics, most of the work goes into taking apart simple components just to get to the tailshaft housing. The hardest thing I encountered was getting the tailshaft housing off after 16 years to service. I resorted to using a narrow flexible putty knife, tapping it into the space between the housing and the tranny to break the seal, then she came off. Nothing came apart or fell out... for those wondering what those mysterious items are that sometimes fall out: they are the parking pawl, the rod it mounts on, and the spring that retains it. Not a bit deal, just put it back in using pics found online as a guide if needed... just make sure it gets in properly or you won't have a park gear anymore, and probably worse.

 

After a week of daily driving I have had no TCU codes, no binding, and great performance. I made a weekend of the project, doing maybe 5 hours each day, but I really took my time. This definitely beat paying someone else to do the work for the money saved and the peace of mind knowing it was done right. Thanks to everyone who helped me out with info, and to everyone else on the board that have posted on this topic before. I was able to go into this whole thing with a lot of info that really helped it go smoothly.