So, my Accord has not been shifting properly. When D4 lights up and stays lit, I can usually shift manually from first to second to D3. If I go to D4 the car might slip occasionally while driving. Lately I've even seen D3 light up and stay lit along with D4.

I pulled the TCU and it looks amazing. No burns, no weird smells, nothing. But I know there could still be a glitch somewhere, because circuit boards.

I checked the codes by jumping the sensor. Check Engine says nothing. D4 flashes continuously. Take out the jump wire, D4 lights up then goes out. Car acts like nothing is wrong and putters along. For now.

What do you think? Should I look at the solenoids as well or just replace the TCU?