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I have a 2011 Traverse with 117,000 miles on it. Just had to have it towed after my check engine light came on. We scanned it at Auto Zone yesterday and the codes above showed up regarding the transmission. Anyone else have this occur and what was the issue? Cost to get fixed? Was really hoping to get another year out of this car. The main codes say shift solenoid A and B control circuit.
 

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Sounds like a change in the TECHM is in order possibly.
By this mileage the laminate discs may be worn also.

The cost-- depends on whether you do it or someone else.
A TECHM is about $200-300.
Theres a thread with many of us who have removed the TECHM.
 

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Delaminated pressure switches will cause these codes. Sonnax sells a kit, about $30. Pull the Techm and swap em out. Good to go after that. (y)
 

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Just so you understand what R barrios and BradM recommend...
Allow me to explain.

Before computers, were invented....... the first calculators, back in the 80's, calculators were made by the great American company Texas Instruments
When you pushed the buttons on the calculator, there was a "dimple switch"
which when depressed
completed the electrical circuit, and when you released the button, the Dimple switch popped the button back up. Like if you pushed the number 4 button, on the calculator when adding 4 +3 =
When you push the 4 button on the calculator , you push down the dimple on the bi metal electrical "switch" , and when you let go of the 4 button the button would spring back up.
When you pushed the button down it completed an electrical circuit, and then like a spring the dimple pushed the 4 button back up , opening the circuit.
Well
that's exact same technology used in TECHUM to tell your car what gear it is in,
There are holes in transmission, kissing off against about 8 switches, and when your car is in say PARK, pressure will dimple down that switch,
Texas Instruments invented the pressure switch manifold idea, in fact, they even used to make it for GM.
Back in 89. Texas Instruments started making these pressure switch manifolds for GM..
today, the TECHUM also has the computer chip, that collects the info from the pressure switch manifold, included inside the transmission as part it the TECHUM..
kinda like an intel pentium chip as part of TECHUM inside transmission

For our transmission, there are a bunch of these bi metal switches, and depending on what great your transmission is, say 3 RD gear, then the 3rd gear dimple switch in the techem will be depressed, and your traverse computer will know you are in third gear.

Usually What failed, is the "Mylar" piece of plastic that covers this bimetallic metal switch...
The golden colored Mylar, which is as thick as 3 sheets of paper, and is kinda like paper, tears over time, and transmission contamination and ? Results in the TECHUM failing.....
Sometimes it is the o-ring type seal that fails....

A mechanic will just replace the TECHUM, a skilled person would buy the $30 kit, and replace the Mylar and o-ring type seals them selves, but you need all the tools... and it requires skill and knowledge...

The TECHUM is a beautiful piece of engineering and manufacturing..... unfortunately transmission fluid is a very harsh environment for the Mylar that protects the dimple switches... which "dimple hundreds of thousands of times" over the life of a car.
 
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