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TCM reflash: is Subaru TSB 16-96-15 the same as Toyota/Scion TSB S-SB-0021-15?

Subaru TSB 16-96-15:

Quote:

TCM Reprogramming File Availability for Engine Idle RPM Fluctuation on 6AT- Equipped Models

This bulletin announces availability of reprogramming files for optimizing the Transmission Control Module (TCM) on all 2015 and some early-production 2016MY vehicles to control an engine idle speed fluctuation condition when in Park or Neutral. The cause is incorrect operation of a back-up program the TCM uses in the event of a turbine speed sensor problem. Affected vehicles may see a fluctuation of approximately 200 rpm (between 600 – 800 rpm idle speed).

Toyota TSB S-SB-0021-15:

Quote:

Idle Fluctuation in Park or Neutral

Some 2015 – 2016 model year FR-S vehicles may exhibit a condition where the engine idle speed fluctuates (typically 500 – 1000 RPM) only when the transmission is in the Park or Neutral shift position. This condition occurs after the vehicle has been driven about 25 miles or more at highway speeds. The Transmission Control Module (TCM) logic has been revised to address this condition. Use the following procedure for reprogramming the TCM.

Those sound really similar, but not quite the same. Reportedly the Toyota TSB TCM reflash fixes the AT rough shifting issue, so I'm hoping the Subaru one is likely to have the same software update.

Quote:

Originally Posted by inio (Post 2589653)

Subaru TSB 16-96-15:

Toyota TSB S-SB-0021-15:

Those sound really similar, but not quite the same. Reportedly the Toyota TSB TCM reflash fixes the AT rough shifting issue, so I'm hoping the Subaru one is likely to have the same software update.

Definitely so, I'm the person who found the original TSB and uploaded it and diagnosed the issue with my dealership techs where I get the car serviced.

The issue was definitely a TCM reflash so these are one and the same, they both involve an idle speed fluctuation problem.

Will getting the reflash done at a Toyota dealership or Subaru dealership matter? Since our transmissions are exactly the same, does that mean that the TCMs are the same as well?