94 4l60e stuck in third gear

[strayauto82]

1994 blazer k1500 all of the sudden stuck in third gear. I can shift down to 1 and get first but not in od. Hard to take off and no upshifts. So pretty sure it's 3rd. Any help diagnosing this?

 

[Supercharged111]

Check your fuse, trans will default to 3rd when it loses electrical power.

 

[NickTransmissions]

1994 blazer k1500 all of the sudden stuck in third gear. I can shift down to 1 and get first but not in od. Hard to take off and no upshifts. So pretty sure it's 3rd. Any help diagnosing this?

Your transmission is in limp mode...As mentioned, check fuse - if it's blown and continues to blow, you have a short somewhere in the electrical system. Check for power at the case connector on the vehicle wire harness connector to ensure power/signal is going to the PCM. If those two tests dont uncover anything, continuity test the transmission's case connector to see if you have any opem circuits that indicate either trans harness or one of the solenoids, etc in the trans (they are all in/on the valve body).

Let us know what you find and we'll go from there...