I have a 1992 honda accord EX and it has a transmission shifting problem. I had a solid lit D4 light on the dash regardless of what gear was selected and the car would only shift if it was put in 1st or 2nd and then only into that gear. When in D4 it would not shift at all, and stayed in what I think was 2nd. I swapped out the trans. Control unit under the carpet today hoping this would fix the problem and instead it made the D4 light blink and made the trans stay in 1st only (2nd if I select it on the shifter)

I now regardless my trans shift solenoids are causing the blinking D4 due to what I have read is common for this car, but I am worried that my TCM my not be working correctly as it was bought used. How can I test the TCM to see if my new or old one works correctly and would a trans solenoid fix my problem?
Please help... anything is better then having to replace the whole trans.

Thanks, matt

WOW we have the same problem. I am getting ready to switch out the TCM, I hope I don't have the same problem as you when I do. I have a friend I worked with that is a Honda tech that says he has seen the TCM die often.