The sport shift light is lit constantly. I have to shift manually from first to second, and the transmission won't go beyond second. This condition was present for a few weeks, and then seemed to spontaneously "fix itself". Now it is happening again. Is this a relatively simple electronic problem? Any help appreciated!

 

This is a symptom of damaged Trans Control Unit. There are two TSB's on this, TSB 017 and TSB 90-039.

Diagnostics
1)Step on brake pedal w/ keyswitch ON. The interlock control unit may stop buzzing or clicking.

2)Reset the AT Control Unit by pulling Fuse 24 in the underhood fuse box. The S light remains off and trans shifts normally.

3) Removing fuse 24 does not clear the AT Control Unit.

Any of above would indicate you have this problem. The AT control unit board may show a damaged (burnt) component.

Try a search of forum for Trans or Transmission problems.

A rebuilt or used TCU should fix this problem, if it's confirmed to be the fault.

good luck

 

Thanks! I pulled the fuse and the TCU reset itself.

 

What happened? Shifting normally & S light off? I would wait to see if S-light comes on again,...likely.

If yes, then a replacement TCU is fix.

good luck