Hi, first time poster here. This is in reference to my 1990 Honda Accord LX, automatic transmission. Recently, the transmission dropped into 3rd (I believe), and wouldn't come out. In reading other threads on this forum, I believe the problem to be the TCU, as I am able to disconnect the negative battery terminal for 10 seconds, then reattach. This takes care of the problem temporarily, as in 2 or 3 days with light driving. I thought the TCU was under the passenger side floorboard, where the feet would be, but all I see there is the ECU, a long rectangular unit, which was replaced in 2009 (that problem turned out to be the main relay, which I replaced myself). My mechanic said the TCU would be under the center console. So where is the TCU? Thanks in advance for any help.

Gary

 

 

Also, see link:

Honda Electronic Transmission Problem- Troubleshoot, Inspection, Repair, Replace.

 

Thanks, redbull-1. That is exactly what I am looking at. So the TCU and ECU are both under that cover, right? Good thing I didn't listen to the mechanic! I have to run for work in a few minutes, but will check it out tomorrow and get the part # off the TCU so I can get one ordered. Thanks again!

Gary

 

Yes, both are located underneath that protective plate.

 

So I got the TCU pulled today and looked at the part number. It is 28100-PX0-921-M1. The TCU I was thinking about replacing it with is 28100-PX4-832. It is supposed to fit a 1990 Honda Accord. Is there some way to check part compatibility?? BTW, some good info in those links above.

Thanks, Gary

 

Does anyone know if the part I listed above will work, or do the part numbers have to match up exactly?

Thanks, Gary