4L60E issues with 1st gear and OD
However, if you are SURE it is shifting from 2nd to 3rd, then it is not limp mode.
If shift solenoid A does not turn on, then you will only have 2nd and 3rd gear. That could be caused by a burnt out solenoid, wiring problem to the solenoid, or a clogged/stuck solenoid.
The burnt-out/wiring-problem will usually give a MIL light and then put you in limp mode.
If you decide to replace the solenoid, you might as well replace both as they are only $12 each and it will likely take you an hour. You also won't mix up shift solenoids A and B that way.








