I bought a 04 cts that was hit in the front the radiator was replaced so i guess it is low on transmission fluid. but it shouldnt be so low that its making my car want to start in 3rd gear. also the check engine light was on so i ran the codes. it says no communication with transmission code U0101. the reverse lights also dont work. i think that may be the relays though which i am replacing tomorow. i know nothing about these cars. i am taking it to get a transflush also and i will see if that helps. but does any one know about that code? thanks...[&:]

 

What color is the fluid? & if there is a no communication code there is probably a bad connection or no connection at all with the trans itself. For it starting in 3rd gear in sure there is a malfunction with the shift solenoids connection and computer since most transmissions go into limp-mode with 2nd gear. I would jack it up n see if you can get to any connections that might possibly be loose. Theremightbe a splash shield here n there but thats easy removal.

Buy a repair manual also. The manual should have wiring diagrams which will make it easier in finding where a particular connector to a sensor is. Or just do it by sight I guess if you choose not to buy the manual.

You will have to fill us in after you repair the taillights n after your transmission flush.