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2010 2.5i Outback, 2015 2.5i Legacy w/Eyesight
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Discussion Starter #1
I have 2 TCM-related questions:
1. Does anyone know whether the TCM's "Learning Mode" can ever clear by itself? Or, is this really something that can only complete by running the appropriate procedure while hooked up to a "Subaru Select Monitor"?
2. Does anyone know if driving the car while the TCM is in learning mode can damage the CVT/car in any way (other than an extremely annoying intermittent dash light)? My car drives/shifts normally, but I need to do some longer (2 hour+) drives soon.

If the answer is model-specific, this for a 2010 Outback H4 with CVT.

Full history on why I ask:
At the end of a 2 hour drive the other day, my dashboard lit up like a christmas tree with AT Oil Temp light flashing, BRAKE light flashing, and VDC light solidly illuminated. Since I genuinely expected it to be a transmission issue (the trans on my wife's 2016 Legacy went at 40k miles and my car just rolled over 170k), I called the dealership since I understand most independent shops don't have the special "Subaru Select Monitor" that can interface with the TCM. They fit me in same day with a $150 out the door diagnostic fee.

Well, this whole thing has left me feeling like an idiot because the dealership let me know that they stongly suspected it was caused by a bad ground from an LED brake light. Instantly, I remembered my from post years ago: https://www.subaruoutback.org/goto/post?id=3281778 Basically, I never went back and put in a load resistor so I could swap both brake lights to LEDs like I had intended all those years ago and had been running with one incandescent brake light and one LED brake light as a "temporary" (eventually permanent) solution since just one incandescent in-line fixed the problem. Well, the incandescent finally burnt out. In any case, the dealership told me they wanted $100 to replace both brake light bulbs (in addition to the $150 diagnostic fee) and then they would continue with any necessary diagnostics afterward. Since they jogged my memory and I was then also pretty certain the LED brake light was the issue, I said no to them doing the brake light service and did it last night for $7 in 15 minutes.

Well, while driving my car home from the dealership last night, I noticed the only light flashing was the AT Oil Temp light and it was flashing intermittently. After replacing both brake lights, there was no change to the intermittent flashing of the AT Oil Temp light (8 flashes with 2 seconds off in between). I looked it up in the Subaru technician's repair manual for my car and basically my TCM is in "AT Lesrning Mode". Below is a summary of the meaning of the AT Oil Temp light's illumination states from section CVT(diag)-22 of the manual:
  1. If the light stays on continuously, the oil temperature is high or the light is malfunctioning
  2. If the light blinks continuously 2 times a second, then the TCM detects a malfunction of the CVT (Note: this was the state the light was flashing in when I brought it to the dealership--I confirmed from a video I took when the issue first appeared)
  3. If it blinks 8 times and then turns off for 2 seconds and repeats this cycle, then the TCM is in "AT Learning Mode" and the only way to get out of it listed in the repair manual is performing the "Learning Control" procedure in section CVT(diag)-20 of the manual which requires commands from a "Subaru Select Monitor"
Basically, I think the dealership cleared the "Learning Control" section of my TCM's memory thinking I wouldn't know or notice the difference in the flashing lights so that I would have to come back to them and pay another $100+ to run the "Learning Control" procedure just to "diagnose" and turn off the light.

In any case, I took the car on several test drives (including the CVT performance test from the manual) and the CVT performs like it should. I did one test drive longer than 30 minutes with a combination of city and highway driving after disconnecting/reconnectong the battery (was hoping that drive time and the right conditions would reset it like with most CELs). I still have the same state of blinking AT Oil Temp light indicating it is in learning mode. I plan on contacting the dealership today, but I would be completely unwilling to fork over another $100+ bucks just to try getting the TCM out of learning mode if it can be achieved another way. If dealership service is required, Im definitely chancing a drive to the dealership I trust over the one that is closest.
 

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2001 VDC/SC One of a Kind
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14,046 Posts
The dealership is not the only place that can communicate with the TCM. I use an Autel MaxiDas 808 to force a learn mode on Subaru CVTs. I believe the SnapOn will also do it.

Where are you???? Surely there are shops in your area that have quality diagnostic scanners. Maybe even a Subie shop (or Subie performance).

It is difficult to get a CVT to complete learning while driving. Too many variables.

What were the codes pulled from the systems on the car? This is important and should be on your diagnostic receipt.
 

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2010 2.5i Outback, 2015 2.5i Legacy w/Eyesight
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595 Posts
Discussion Starter #3 (Edited)
Well, the dealership told me that they performed clear memories on the TCM, but were unwilling to run the "Learning Control" procedure unless I paid $300 for a transmission fluid change or $150 for just the learning control procedure where I would sign a form indicating I declined the CVT fluid change. This was even after I showed them in the Subaru repair manual for my car where the need to perform "Learning Control" arose only because they cleared the memory on my TCM.

The original issue was a bad ground connection caused by a poorly designed LED brake light and I realize that a bad ground connection possibly could have put my car into learning control mode. That said, the dealership explicitly told me that they cleared the TCM which most definitely requires "Learning Control". I would have been willing to pay to fix it there if they were unsure whether they cleared the TCM memories, but since they were sure that they cleared the TCM,s memory, I thought it was reasonable that they should perform Learning Control free of charge.

I am in Northeast Ohio and this was at a Ganley delearship (one of the biggest dealership names for all car brands in the area). Needless to say, if a car repair shop creates a problem and then wants to make me pay to fix it... I left and will never be back. I went to another dealership that is 40 miles away and had a great experience there. I ended up paying $140 out the door (minimum charge for a "software change") to the other dealership to initiate learning control on my TCM and fix Ganley's screw-up. Car ran just fine all the way to the other dealership--it must either run with a stock profile or the TCM's non-volatile memories aren't actually completely erased by the "Clear Memories" call. That said, no more blinky AT Oil Temp light and I know where I am taking my car for major service next.
 

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19 Outback 2.5i Premium
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I'm still wondering if the old trick of disconnecting both leads to the battery (positive and negative), then touching the leads the leads together for a while will clear out the codes and make the systems go back into learning mode works?

Just remember when touching the leads together to NOT include the battery, what-so-ever!!!

This used to be the "poor mans way" of clearing codes and settings, before we could get our hands on OBD II readers and such.

Actually I did this on my OB, because one day not long after I bought my used OB I tried to accelerate quickly and the engine RPM went up but the car didn't accelerate very quickly and kinda died. It felt like the transmission was slipping.

So I disconnected battery, and touched the leads together and went in the house, watched an hour show, came out, reconnected the battery, reset the power windows, and went for drive. One hour out on the freeway (half of the trip with the AC off then on), and drove back home via the surface streets (again half with the AC off and half with the AC on). Now the car runs like a champ and accelerates really well.
 

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Premium Member
2001 VDC/SC One of a Kind
Joined
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14,046 Posts
I'm still wondering if the old trick of disconnecting both leads to the battery (positive and negative), then touching the leads the leads together for a while will clear out the codes and make the systems go back into learning mode works?

Just remember when touching the leads together to NOT include the battery, what-so-ever!!!

This used to be the "poor mans way" of clearing codes and settings, before we could get our hands on OBD II readers and such.

Actually I did this on my OB, because one day not long after I bought my used OB I tried to accelerate quickly and the engine RPM went up but the car didn't accelerate very quickly and kinda died. It felt like the transmission was slipping.

So I disconnected battery, and touched the leads together and went in the house, watched an hour show, came out, reconnected the battery, reset the power windows, and went for drive. One hour out on the freeway (half of the trip with the AC off then on), and drove back home via the surface streets (again half with the AC off and half with the AC on). Now the car runs like a champ and accelerates really well.
With the CVT, any memory clear/reset of any kind will require a relearn to be initiated with a scan tool. I've yet to get a CVT to relearn on just a drive, whether on the road or on a lift using Subaru's posted procedure. The scan tool method takes about 15 on a lift.
 
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