Last 2 days on a cold start. Shift to D4 and take off. Slow acceleration (like accelerating in a manual from too high a gear) from stop and no auto shifts at all. D4 light on. AtALL other gear shift positions D4 remains lit alongwith other indicators. When I manually drop to 1at astop the car does downshift.It doesaccelerate normally (since its in 1) it does upshift when I manually move to 2.At D3 and D4, no shifting. On a normal stop and startin D3 or D4 car does NOT downshift automatically but remains in 2. Then abruptly some time later car begins shifting normal.

1st time it took maybe 15min to work then today a good hour. Today restarted after 3 hours and all OK.

I did take it to a tranny place for diagnostics. Just wondering what any of the board experts here might think it is so Im informed when I hear back from tranny place.

Thanks.

 

Well why not go ahead and jumper the blue 2 pin service check connector behind the passenger side kick panel, then turn on the key and see if the D4 light gives a flash code.

FWIW I've found that if the D4 light is on there is usually some kind of electrical/TCU problem

 

Hondadude...

Tranny place said code was for "speed sensor failure or break in circuit" but did not know where that break would be. Advised me to take it to Honda dealer for diagnostics as they would better know where a break could be and I would not have to pay tranny guy hours to find it.

SO...car to dealer this AM. They called me back and said codes show Transmission Computer failing intermittently, $750.Sounds logical since car ran fine on way to dealer, but OUCH.

Call guy I bought car from says he can find a computer and replace for around 200.

Is this Transmission computer what you referenced above....as TCU problem?

 

One more ?. As I mentioned above the tranny guy mentioned reading the trouble code as "vehicle speed sensor/break in curcit".

Could that be the samething the honda dealer diagnosed as "transmission computer failure"?

Thinking no but Im not the mechanic.

Would it be advisable to have BOTH the TCU and Vehicle Speed Sensor replaced?

 

Finding the code is pretty simple to do. All you need is a paperclip and the ability to count. The instructions on CEL can be found here http://www.dhost.info/accordinfo/ Just count the D4 flashes.


Anyway, TCUs normally do not fail. I would replace only the VSS and see if you still have problems.