92 automatic transmission controller

My 92 Accord LX sedan auto transmission (the standard one not the fancier
version) will not shift out of 2nd gear (for a while it was staying in 3rd
gear). Reverse works fine. The dash lights show multiple lights at the same
time, usually the 4th gear indicator is on along with the one you are shifted
into. For example when first turning it on the park and 4th gear lights are
both on. Fluid is pretty new (Honda fluid). This is the third time this has
happened over the last year but the first time it has not fixed itself in a
couple of days.

I'm told it is probably the computer. Is this likely and if it is where is
it located. I called a junkyard and they will sell me one for $20.00 but I
have to dig it out myself. Is it worth the effort to try to swap the
computer out without professional on-site diagnostics to confirm what the
problem is?

Thanks for your help.

 

I have a 91 Accord that was in a foot deep puddle and I ended up
frying the computer. Thanks to the folks on this board, I was able to
replace it with a junk yard computer for $60. Honda wanted $951.

The main computer, which I fried, and the AT computer, are both
located under the floor where the front passenger feet rest if
extended forward. It's where the floor rises up. Pull up the carpet,
and you need to unbolt the metal plate; both computers are on the back
of that plate. They're metal boxes about eight inches by eight inches,
and maybe two inches deep. They're each connected to the wiring
harness by two or three connectors.

The AT one is the one closer to the driver side as I recall. They
aren't really easy to get out and I had to buy a deep socket set
because the nuts are tough to reach. The screws project about 1.5
inches and only a deep socket could get them. I think they're 10mm.
But after 1 1/2 hours of cursing, I was able to plug in the junkyard
one and the car started right up. Of course, I still had to throw
about 50 lbs of cat litter onto the floor to dry out the carpets but
that's likely not something that you'll need to do.

I have no idea if this will cure the problem, but all you're out is an
hour or two of work and $20 if not.

 

It could also be one of the sensors in the engine compartment such as the
throttle position or engine temperature. Fold back the carpet as mentioned in
other messages. That will expose the LED fault indicator. (The little carpet
flap covers the LED indicator for the engine computer. You must pull back the
carpet to see the transmission computer LED.) When you first turn on the
ignition switch (you don't actually have to start the engine), do either of the
lamps flash? If they do, count the flashes. That will tell you where the
problem lies or at least where the computer thinks the problem lies.

 

I dug the old AT controller out of my Honda and headed to the salvage yard
where I found a used one for $30.00. I plugged it in and even though it was
from a 93 Accord instead of a 92, it works great. Thanks for everyone's help.
...Dan