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No AWD steelership diagnosed as duty c and clutch pack, replaced but still NO AWD


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Maybe someone put the FWD fuse in, then pulled the light out of the dash?

 

You say you checked the duty C signal, how? If you just measured the voltage, that's not giving you an accurate idea of what's going on. It's a 50hz pulsed signal. So you need to check it with an o-scope or meter that can tell you what the signal is. If the duty C is getting full power, that's fwd.

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if you cut the power to the duty c and still have no power to the rear, then you have a mechanical problem.

 

either in the transfer clutch, drive shaft, the rear diff, or the axles. probably the transfer clutch.

 

are both rear axles in tact?

 

does the CEL light up with the other dash lights when you turn the key to on?

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all dash lights work properly FWD fuse puts car in FWD mode with illuminated FWD mode light.

 

NOW I have a BRAND NEW solenoid in the car so I KNOW its good being a subaru part from a subaru dealer.

 

after installing the new solenoid the mil for the at oil temp stopped flashing and would not output any codes via the TCU handshake and mil flash procedure.

 

since I watched the parts go in I know there is not problem with the clutch packs it has to be the drive hub not getting power from the trans..... its not like I'm getting binding of the rear end its completely loose and I can spin the drive shaft while the car is on jack stands INDEPENDENTLY OF THE FRONT wheels.

Thats something I asked to be checked but was NOT.

 

all axles are intact as well as clean oil in the center diff. the jack rump roast or mechanic who helped me buy this car failed to tell me the awd system was ************ed I paid him to evaluate the car and make sure it was at least repairable and he apparently works on subaru's all the time at a reputable shop. all he did was look under the car and see all the part casings and said "it should work". I should have at least lifted the car up in the rear to check that the back axles did not more independently of the front.... I guess you live get ripped off then learn....

Edited by bluedotsnow
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if you cut the power to the duty c and still have no power to the rear, then you have a mechanical problem.

 

either in the transfer clutch, drive shaft, the rear diff, or the axles. probably the transfer clutch.

 

are both rear axles in tact?

 

does the CEL light up with the other dash lights when you turn the key to on?

 

so your saying a problem from the trans could NOT cause lack of awd????

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Wow what alot of mess oly thing i can add is that subaru turns off the voltage to the soiliniod to engage awd not power it to turn on awd . when the soiliniod is off flows into awd cuircut when powerd it dumps preshure.When 2wd fuse is in it powers the soiliniod and dumps line preshure so no flow to awd. I run thiss tranny in dragster i tookout whole awd valve assembly and ran a soilid line to awd strait line preshure all the time my awd do's not slip at all. One more thing the less clearance the clutchpack has the sooner it comes on i set them 1-2 thow or less tighter is good but must still have clearance i custom set clutch packs to customers driving needs and location. some people need more awd than others.

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I have read about how the trans operates the clutches with line pressure and clutch engagement. I'm nearly positive the clutch system is operating properly as no mil lights turn on that are not supposed to or when they are not supposed to. PLEASE correct me if I'm wrong but the clutch engagement does nothing if the drive hub is not connected to the trans ie sheered or snapped. I have checked the ATF no metal shavings.

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I'm getting binding of the rear end its completely loose and I can spin the drive shaft while the car is on jack stands INDEPENDENTLY OF THE FRONT wheels.

Thats something I asked to be checked but was NOT.

That's how it works. When the car isn't running there's no line pressure to the clutches, therefor the driveshaft will just freewheel.

The clutches require pressure to give power to the back wheels.

 

Same goes when the engine is running, it doesn't matter what the duty C is doing, if they aren't getting pressure, no rear wheels.

 

That's why someone suggested you unplug the TCU and try to drive the car. With the TCU unplugged the transmission goes into limp mode. Meaning it can only use 3rd gear and reverse. And no power goes to the duty C, so it should be in full 4wd lockup. You'll know if it is, the binding is pretty severe even on dirt when you turn.

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That's how it works. When the car isn't running there's no line pressure to the clutches, therefor the driveshaft will just freewheel.

The clutches require pressure to give power to the back wheels.

 

Same goes when the engine is running, it doesn't matter what the duty C is doing, if they aren't getting pressure, no rear wheels.

 

That's why someone suggested you unplug the TCU and try to drive the car. With the TCU unplugged the transmission goes into limp mode. Meaning it can only use 3rd gear and reverse. And no power goes to the duty C, so it should be in full 4wd lockup. You'll know if it is, the binding is pretty severe even on dirt when you turn.

you missed the ITS NOT LIKE before I'M GETTING BINDING.

 

I should have said when the car is in drive and on jack stands...... I can spin the shaft freely.........

 

pulled tcu drove, NO BINDING the only difference was the ABS light illuminated from the start. and of course 3rd and reverse were the only gears.

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pulled tcu drove, NO BINDING the only difference was the ABS light illuminated from the start. and of course 3rd and reverse were the only gears.

 

Then you most probably have no line pressure to your clutch pack. When they changed the duty-c did they replace the valve body and both of the gaskets on the orifice plate under it?

 

GD

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I received the solenoid with valve attached it has a gasket already in place between the main housing and a metal plate and an additional gasket used for mounting to the housing.

 

I though no voltage caused a bind? hence why when the duty c fails it causes bind and eventually damage to the drive line. when it is energized more it causes more front wheel bias.

 

is there any way to test the line pressure from the duty c to the clutch packs?

 

are there any other hard parts that could have teeth missing and or gone? this is a high mileage Subaru

Edited by bluedotsnow
I misstated, I meant voltage
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I got the solenoid with valve attached it had a gasket already in place between the two pieces of valve housing in addition to a loose one that went between the tail housing and the valve.

 

I though no voltage caused a bind? hence why when the duty c fails it can cause bind and eventually damage to the drive line.

 

And no power goes to the duty C, so it should be in full 4wd lockup. You'll know if it is, the binding is pretty severe even on dirt when you turn.

 

I already said that. That's why GD said you probably don't have pressure at the clutch pack.

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There is a bung on rear tail housing to check preshure put a gauge on it and c i did have one break the transfer line that moves fliud to rear of tranny is a 3/8 meatal line above the valve body on mine it just vibrated and broke but very rare. I doubt the basket sheard the splines theese are very tough and have only seen one sheard was on svx that was being neutral droped many times and still sorta worked even with sheard spline thiss makes a mess would see meatal in pan

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I received the solenoid with valve attached it has a gasket already in place between the main housing and a metal plate and an additional gasket used for mounting to the housing.

 

Some of the holes on that plate are very small. Was the plate removed and the gaskets on both sides of it replaced after fully cleaning and polishing the plate? I clean them with a roto-loc disc in my die grinder because the gaskets get stuck to the plate and don't easily come off.

 

I though no voltage caused a bind? hence why when the duty c fails it causes bind and eventually damage to the drive line. when it is energized more it causes more front wheel bias.

 

No voltage causes full line pressure to be sent to the clutch pack - which causes them to lock. Full voltage (100% duty cycle) unlocks the clutch - by cutting off the line pressure. But the same thing will happen regardless of the voltage to the solenoid if there is no line pressure for it to lock the clutch pack with.

 

is there any way to test the line pressure from the duty c to the clutch packs?

 

As Ivan noted above - there is a plug on the extension housing where you can check line pressure to the clutch packs. You will have to look up what that pressure should be - I don't know it off the top of my head.

 

are there any other hard parts that could have teeth missing and or gone? this is a high mileage Subaru

 

Extremely unlikely. And you would have seen massive amounts of metal in the extension housing when it was removed and metal swirl in the pan fluid.

 

GD

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I will check the line pressure ASAP is this something you have to pull the exhaust and drive line for? can I get to it with out taking anything apart with the car on jack stands?

 

I don't think they used to scotch bright rotto resurfacing tool on the housing under the solenoid but they did clean it and cleaned it with a razor blade. I have noticed how tiny some of the ports are especially directly under the solenoid. they did use the rotto tool on the other gasket areas around the tail housing gasket.

 

I have been looking for a flow diagram for just the solenoid, if anyone has one or knows where one is located I would love too see it. I know this is a long shot but basically a picture of where and how atf flows in and out ,ie what channels carry atf in, which channels are the dump off or fwd channels, and which send atf to the clutch pack.

 

many thanks my mind is more at rest... and I'm more determined than depressed for a change!

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Still waiting on an opportunity to check the line pressure as this is out of my abilities. Can any mechanics who use all data tell me if the clutch replacement process requires verifying the drive hub is attached and will not spin? does the process also require checking of the line pressure to the clutch pack as described by GeneralDisorder?

 

I'm trying to verify that winters auto did do everything right as I would hate to cast blame on someone who does not deserve it.

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please remember these facts.

 

I just bought the car.

 

it needed head gaskets at the time

 

I was unable to test the AWD function untill after heads were rebuilt

 

the car was sitting for a year or so before I got to it and was actually missing the fusible link.

 

someone could have been in the trans way before I bought it found a blown out shaft cleaned it all up put it back together and let it set.

 

I feel a slight slip when I step on the gas not in the front as the tires start to move but it feels like where it should grab in the final drive for the rear end there is slippage. I thought this was something subaru would address it did pass a drivability test but they likely did not take it out of limp mode to test and only assumed 10% drive was going to the rear and never actually checked it.

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I guess its possible that the old clutch pack wore the casing away and needs a larger one subaru of america however told me they would only warranty a 3.3mm clutch pack as that's the original part and the only size they recommend for my lego...

 

I did get a chance to look at the output shaft and seal ring and they looked undamaged. I don't see any atf leaking anywhere!

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