Thread: honda auto tcu help

So yesterday my 1990 automatic Accord goes into limp mode. Flashing S light (Sport light for trans). Speedo also starts working off and on.

Googled the symptoms and found that a common problem on these cars is that the tcu (trans computer) craps out. Read that you can open up the tcu and look for burnt resistors or buldging capacitors, and then replace those instead of dropping $150 for a rebuilt tcu which im trying not to do because in other news I later rear-ended a lady yesterday. . Not my day I guess.

So I pulled my tcu out today and opened it up. I cant see anything wrong with it but I have zero knowledge of electronics. Was hoping maybe some one had some pointers for what I should be looking for.

The only thing that looks suspicious to me is the buldging on the back of the big brown rectangles:



Not sure if that is how they are supposed to look.

everything appears good.

flip the board over and make sure all of the connections are good on that side. all of the sodering should be done on that side, maybe something came loose.

check the pins on the harness side and the tcu side to make sure everything is tight, straight, in place and what not.

Thanks for the tips. I flipped it over and nothing looks like it came loose.

Put the computer back in the car and checked for codes. I think its giving me a code for the vehicle speed sensor so im going to start there. The board looks fine but I read one person say theirs looked fine and that in his case you couldn't see that the capacitor was damaged until it was removed.

read once that sometimes the vss and tcm crap out at the same time but couldnt confirm that anywhere else.

had no idea this gen of accords have so many trans related issues. Been researching and wow.