I have a 2001 Accord EX, 4cyl. ONLY when it's below freezing, I get a CEL and the transmission will only work manually. It has an automatic and I have to put it in '1' and manually shift up for it to roll. It will stay in '4th' otherwise. I hit the rev limiter, protection mode. When I check the codes, the code says replace the PCM. Transmission wise, I've changed the fluid, twice, and replaced the shift solenoids; no difference. I love the car and once the temperature outside warms up over say 40 F life is good.. Once it's below 32F, here we go again.

 

I moved your post to a new thread. The original thread is over 11 years old, so it is better to start a new thread.

What is the actual code you are getting, like P1234.

 

The code is P1607

 

P1607. Thanks

 

If you get the inside of the vehicle warmed up, do you still have the shifting issues?

 

yes. It only gets 'normal' once the outside temperature gets above freezing. Engine/tranny temp has no effect.

 

I'm asking if the cabin air temperature (where you sit) gets warm, does the transmission shift normally?

 

The cabin temperature makes no difference. as long as the CEL is on, when shifting from 'P' to 'R', the trans SLAMS into gear. When shifted to 'D', it goes to 4th and stays in 4th, Once the outside temp goes above freezing, the transmission shifts normally. the only temp that makes a difference is the outside temp.

 

Once the CEL turns on, the PCM may continue to malfunction. It is worth a shot when you have frigid temperatures to let the car warm up and the cabin get hot. Turn off the engine, maybe disconnect the battery to reset the PCM, then try to restart the car. The PCM sits inside the cab, so maybe having the inside warmed up will expand a solder joint to make a proper contact?

 

Great idea, I'll give that a try. It seems the long term solution is to replace the PCM. It would seem the PCM ultimately controls the transmissions' shifting.. Not necessarily the transmission itself.