Subaru CVT TCC Lockup Fix - Done

Joined
Dec 17, 2011
Messages
395
Location
Northern NJ
In case it helps anyone - on our original owner 159k mile 2012 Impreza, the dreaded 0700 and 2764 codes were thrown a couple weeks back. (think they throw 2763 sometimes. Car was stumbling coming to a stop as well, kind of like the converter was stuck locked, but I also cleaned up a bad idle at the sime timeby cleaning the throttle body, so unsure if the stumble was the same problem. The trans worked perfect at speed even with all the dash lights that went off. It even was flashing overtemp trans but it really couldn't have been.

In the redesigned '12 Impreza, this is the second generation 'TR580' CVT. In this unit, at least I think '13 back, there are two known problems. One is the torque converted itself physically has a thrust washer that goes bad and impedes release of lockup. Reman torque converters are available with a full on bearing in place of the washer.

The more common, I believe, problem is the TCC solenoid in the valve body. The valve body is removable from the engine compartment, firewall area (its below a cover plate on top of trans.) Take out the air tube, 'dog bone' and you can pretty much go at it. Subaru only sells a complete valve body and then does expensive fluid service and computer learning.. reportedly minimum bill of $1500.

Aftermarket has the TCC solenoid for $100-$150. I bought the one on Amazon even though it was more expensive, just in case, due to specific reports of successful uses of that one. There's ones on ebay closer to $100 and some other places. Book labor to R&R the valve body is just over 2 hours and I was pretty close on that part. I ended up spending a lot of time on the solenoid replacement but there's nothing all that hard and you are not taking the valve body apart but just some bolts, removing a plate that holds down 4 of the solenoids. When you take the access cover plate off, beware there are two pin-dowels so after bolt removal you need to pry up- I hadn't know so I banged the cover a bit, thinking it was stuck to the mating surface.

My old solenoid didn't 'ohm out' bad at all actually. Spec is about 12 ohms and some fails apparently are low impedance. Some warned it also may only be bad when hot, and then possibly 'open', and I did seem impedance going a little high with a heat gun, but only like 15 ohms. Regardless, the fix seems to be 100%. Because of the top access, there is no or negligible fluid loss - I didn't adjust it for the trace loss. Picture is of the back or down side of the valve body with the hold down plate and the TCC solenoid out. There is a bit of trickiness with the wires - at first it looks hard wired and that may be even one of the excuses Subaru uses for selling only a complete valve body. But three small screwdrivers carefully pries a cap off, revealing spade terminals.

B9F42751-2BBE-42C6-8328-8BE92615E808.jpeg
 
Impressive how these seem to be getting more serviceable as time goes on.

It's beyond what I would want to do.. though it might be within limit of what I would attempt and succeed at.
 
Originally Posted by Rand
Impressive how these seem to be getting more serviceable as time goes on.

It's beyond what I would want to do.. though it might be within limit of what I would attempt and succeed at.



Subaru is pretty eager to warranty them out. "Oh you have a small pan seep, new CVT for you!" or in the case of the torque converter or valve body, immediate replacement. However, what Subaru usually doesn't see is the complete failure that the Nissan units were having. In a lot of cases, getting the thing working again is user serviceable.

I believe that is because Subaru uses separate lubricant for the differential. Just a theory, though, based off of what I have been seeing when people tear them down.
 
Originally Posted by deanm11
In case it helps anyone - on our original owner 159k mile 2012 Impreza, the dreaded 0700 and 2764 codes were thrown a couple weeks back. (think they throw 2763 sometimes. Car was stumbling coming to a stop as well, kind of like the converter was stuck locked, but I also cleaned up a bad idle at the sime timeby cleaning the throttle body, so unsure if the stumble was the same problem. The trans worked perfect at speed even with all the dash lights that went off. It even was flashing overtemp trans but it really couldn't have been.

In the redesigned '12 Impreza, this is the second generation 'TR580' CVT. In this unit, at least I think '13 back, there are two known problems. One is the torque converted itself physically has a thrust washer that goes bad and impedes release of lockup. Reman torque converters are available with a full on bearing in place of the washer.

The more common, I believe, problem is the TCC solenoid in the valve body. The valve body is removable from the engine compartment, firewall area (its below a cover plate on top of trans.) Take out the air tube, 'dog bone' and you can pretty much go at it. Subaru only sells a complete valve body and then does expensive fluid service and computer learning.. reportedly minimum bill of $1500.

Aftermarket has the TCC solenoid for $100-$150. I bought the one on Amazon even though it was more expensive, just in case, due to specific reports of successful uses of that one. There's ones on ebay closer to $100 and some other places. Book labor to R&R the valve body is just over 2 hours and I was pretty close on that part. I ended up spending a lot of time on the solenoid replacement but there's nothing all that hard and you are not taking the valve body apart but just some bolts, removing a plate that holds down 4 of the solenoids. When you take the access cover plate off, beware there are two pin-dowels so after bolt removal you need to pry up- I hadn't know so I banged the cover a bit, thinking it was stuck to the mating surface.

My old solenoid didn't 'ohm out' bad at all actually. Spec is about 12 ohms and some fails apparently are low impedance. Some warned it also may only be bad when hot, and then possibly 'open', and I did seem impedance going a little high with a heat gun, but only like 15 ohms. Regardless, the fix seems to be 100%. Because of the top access, there is no or negligible fluid loss - I didn't adjust it for the trace loss. Picture is of the back or down side of the valve body with the hold down plate and the TCC solenoid out. There is a bit of trickiness with the wires - at first it looks hard wired and that may be even one of the excuses Subaru uses for selling only a complete valve body. But three small screwdrivers carefully pries a cap off, revealing spade terminals.



Congrats ! :)

Best wishes
 
owners are the beta testers even now as Subaru wants an untouched unit if in warranty so they can learn how to improve problematic CVT's! 3 pedals ALWAYS for me although conventional automatics are generally reliable.
 
Originally Posted by benjy
owners are the beta testers even now as Subaru wants an untouched unit if in warranty so they can learn how to improve problematic CVT's! 3 pedals ALWAYS for me although conventional automatics are generally reliable.


Ironic, but I've always sought out manual transmissions. And I've had more problems with manuals over the years than automatics oddly enough.
 
Reviving this a bit to hopefully get some insight
12 Impreza 2.0 137xxx miles had the dreaded converter lock up solenoid malfunction code replaced the solenoid.... no good replaced the valve body....... no good had a Subaru tech advise it may be the converter itself so yesterday out it came and new one in. And bam !!! 3 miles later and my dash Christmas trees back on!!!!! Not a happy camper. Same malfunction code it runs perfectly, I’m at a lose I’m thinking it may be a wiring issue. If I run live data while driving the duty solenoid percentage will fluctuate as it should depending on throttle position then it drops to zero and stays there then the code pops. Any ideas are muchly appreciated
 
Reviving this a bit to hopefully get some insight
12 Impreza 2.0 137xxx miles had the dreaded converter lock up solenoid malfunction code replaced the solenoid.... no good replaced the valve body....... no good had a Subaru tech advise it may be the converter itself so yesterday out it came and new one in. And bam !!! 3 miles later and my dash Christmas trees back on!!!!! Not a happy camper. Same malfunction code it runs perfectly, I’m at a lose I’m thinking it may be a wiring issue. If I run live data while driving the duty solenoid percentage will fluctuate as it should depending on throttle position then it drops to zero and stays there then the code pops. Any ideas are muchly appreciated
Any update here?
 
Well kind of narrowed it down to the $1.29 O ring that goes on the converter input shaft just haven’t the enthusiasm to drop the trans again to replace it once I do I’ll report back. But a subbie tech help me narrow it down to that........ at least keeping my fingers crossed
 
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