I am the proud owner of a 97 Blazer 4.3,AT..... I have already determined that my problem is electrical and that it has caused my transmission to shut off (lock into 3rd gear) so I have no up or downshifting. I do have reverse. I have pulled the codes from the computer and there are four of them. Here they are
1. Shift cyl. circuit A Malfunction
2. Shift cyl. Circuit B Malfunction
3. TCC malfunction
4. Manufacter Transmission malfunction
I am going to assume that 4 problems just do not suddenlly appear all at once. I am thinking that they are all caused by one common problem however I cannot figure that part out. Has anyone experienced a simaler problem. Please any advice will help.

 

Call a trans shop and talk to a tech. He can get you going in the right direction.

 

Thanks,

 

I have called 6 trans shops and they all say that I need to replace my shift cyls and the TCC. From what I have seen fom other forums I do not think this will resolve my problem. Any other ideas

 

Unless those forums were tranny forums, I would tend to believe what the experts are telling me.

 

Well if you don't trust the Tranny "experts" then who do you trust...Forums can only point you in the direction that you should look into. Your codes indicate that 1. the TCC (located in the valve body) needs to be replaced, it controls the torque converter lockup signal and if it fails then the computer may go into limp(default mode)...it also uses fluid pressure to determine and electronics to lock up the torque converter...but unless you take it to a Tranny "Expert" then you can sit with your tranny in 3rd all day long...

 

That was a bit harsh, but to the point.

 

I agree with 20Blazer00, I would start with the TCC (not very expencive) and easy enough to change out if you know what you are doing. That would be a good starting point. I have seen the TCC's take out tranys. They are also a known issue with the Hydro-Matic and other (that use the TCC system)tranys from GM.