I found this forum through a general Internet search and I must say that I am thoroughly impressed at the level of knowledgeable responses. I have read through most of the Accord posts that relate to transmission problems, but have not found anyone with my specific problem. So here goes... (if it's already been posted, I'm sorry for the repeat but search didn't return anything!)

Auto Transmission

Car runs fine most of the time. While running along at various speeds, the S light will come on by itself and the transmission will immediately downshift a gear (from o/d back to 3rd). While the light is on it stays in 3rd. If the light stays on, then the tranny will not downshift and will start off in 3rd gear (I can manually shift it to 1st and go through the gears that way). When the light goes out, everything is back to normal which leads me to believe that there's a sensor or something that is going bad and not the transmission. After watching and listening closely, I have noticed that when the S light goes out, the shift lock clicks (the same click that you hear when applying the brakes while in park which unlocks the shifter).

I've had the stealership look at it and they claim that they cannot find a problem. I had another mechanic look at it and he says that there's no transmission codes showing up.

Any ideas??? thanks in advance!

 

Do you have a CEL on? (check engine light)

 

Not now. The CEL was coming on and off, but after a mechanic checked it out, it turned out to be the O2 sensor. Replaced it and the CEL has been off since. Transmission problem was existing before and after CEL.

 

Ok, so when the S light comes on are there any other lights...does the S light blink or is solid?

It might be a bad solenoid.

 

There are no other lights that come on. The S light is on solid as if I had engaged the Sports mode even though I haven't.

 

It's also been suggested to me that it might be a bad speed sensor. Thoughts on this??

 

Usually a VSS when it goes out it usually doesn't effect the tranny, your speedo won't work but it will have the s light blink and throw a CEL.

I would look into the solenoids.

 

Okay.... had the solonoids checked. All were clean and all were working properly. Next step I'm trying is to change out the transmission computer to see if there's a problem with that.

Still don't understand the shift lock not working when the S light comes on and the car starts acting up. As I said earlier, while watching and listening, I heard the shift lock engage when the S light finally went off.

Is there a solonoid that controls the shift lock (in the console) that would also affect the Sports mode or vice-versa??

 

It absolutely has to do with a computer glitch or the sensor sending the signal to the computer...the ECU is telling your transmission to upshift...

 

there should be a selenoid near the shifter. check that out. see if it helps. while u there u might wanna check the things that show D1 D2 D3 D4.

 

Okay. changed out the transmission computer with a "shop" computer to see if that was the problem. Cleared up initially, but started back doing the same thing so it's evidently not the computer. Just in case though, I read on a previous thread that if the computer is bad that it's usually a resistor or a capacitor on the board inside. Does anyone know exactly which components? Is there a schematic available for the computer itself? I used to work on electronic equipment (component level troubleshooting and repair) so I feel fairly comfortable around soldering irons and test instruments.

Any more ideas of what could be the problem?? Could the solonoid in the console be the problem? Does it control the Sports mode as well?

Thanks for the help folks! You might just save me a bunch of money and I don't mean by switching my car insurance to Gieco!!

 

go to http://www.cb7tuner.com its only for 4th generation accord. there is a thread that tells u what u looking for.
and if u can't fix it. there is another thread that shows how to swap the automatic tranny by ur self.
(the site is down for a while so u got to wait)

 

Okay.... cracked open the computer box and found a 15 ohm resister burned and a 33mic capacitor that had puked on the board. It looks as though they are in the voltage circuit of the pc board. If that's the case then the rest of the board past that point couldn't get any voltage and hence couldn't send the signal to shift gears. The reason it worked when it's cold is that the resistor was closing when it was cold and opening after the board got some heat to it. Looks like the capacitor probably began shooting its wad and the resistor finally gave up the ghost. I've replaced those and will reinstall the computer tonight.

Fingers are crossed.........................

 

For future reference to anyone searching these boards for the same type probelm, my fix for the problem worked. I replaced the repaired computer and the transmission is shifting just fine.

$3.17 fix and a littel time in diagnosing and fixing the problem vs. $550 for the computer and another $150 for labor. Looks like I got away lucky!!

 

good job. glad you found out what the problem was, did some diagnosing, and figured out HOW to fix it.