Please Help. I have a 97 accord 4cyl VTECH. I have been having issuee with my transmission. It drive and shift judt fine when first turn car on in morning. After 10 min it will go into "LIMP MODE" aka while in drive it will just run up the RPM and not move. If I turn the car off wait a few minutes then back on I can get a few more miles but seems to stay in 1st gear.

Noticed Radiator fan motor was bad thougt maybe tranny fluid getting to hot to switch the gears properly, Replaced that and problem still exitis. Hooked up to comp found out Shifting selenoid A was bad. Replaced that still same problem and D4(flashing) and Engine light was still on. Got another Shift seleniod and also replaced the seleniod b and c combo. D4 no longer flashes, and that code was cleared. Still same problem with shifitng. New code P0700 TCU/TCM.

My question
1) is could it just be that I have to replace the TCU??
2) Does ti have to be exact year and engine?? Say if i get one from junkyard.
3) Read somewhere that if you replace TCU then HONDA DEALERSHIP has to reprogram key ignition and all that. Is this true??
4) Can i just reset the comp ie. disconnect battery for 30 min, or pull the ECU FUSES?? (read that somewhere)


Also, when pulled battery RADIO now needs code. Is the only way to get the serial number for the radio is pull the whole thing out???

ANY HELP IS GREALTY APPRECIATED.. THANK YOU IN ADVANCE.

 

Here are answers to your questions in order.

1) is could it just be that I have to replace the TCU??
Yes
2) Does ti have to be exact year and engine?? Say if i get one from junkyard.
You need the PCM (combination ECU and TCU) from a 96 or 97 4-cylinder automatic EX.
3) Read somewhere that if you replace TCU then HONDA DEALERSHIP has to reprogram key ignition and all that. Is this true??
Not for the 97 accord. Programming the key started in the 98 accords.
4) Can i just reset the comp ie. disconnect battery for 30 min, or pull the ECU FUSES?? (read that somewhere). You can and should try resetting the PCM. Then recheck for codes. Disconnect the battery or pull the 7.5 amp backup/radio fuse in the engine bay fuse box. Both methods will reset the PCM

For the radio code, you may have a sticker on your glovebox with the code, or it could be written in the owner's manual. My 95 accord came with a plastic card with the radio code on it.

 

Thank You PAHONDA..
Where is the Combo PCM? UNDER THE PASSANGER KICKBOARD?

Also if I look for the COMBO PCM 96, 97 EX on ebay is there a part #. I am finding a bunch that say those years, however not that they are from the EX MODELS..

Radio i looked everywhere, glove box, driver side door frame, truck frame. I know the webstie to go to but need the serial number and fining its going to be a pain to get to the back og the radio.

Finally, I think it also throw me a O2 oxgen code.. Not sure have to ask my friend that gas been helping me. Could a O2 sensor also be giving me these t=same problems with the Shifting.. And I to be sure its not a whole tranny rebuild problem?

 

The PCM is under the metal panel on the passenger floorboard near the firewall, like the 90-97 accords. For the part number, go to hondapartsnow.com and look it up with your vehicle info. The ECU/PCM is listed under Electrical / Exhaust / Heater / Fuel > Control Unit (Cabin).

I think the part number will be 37820-P0H-L54. You should enter your car's info to verify. Not sure if your car was for California emissions or not.

You definitely need to write down all codes and can post the codes on here. There are many O2 sensor codes that could cause some issues. P0700 was not listed in my shop manual, but P07xx codes tend to be transmission codes.

 

This is a huge help. I will repost the codes it reads me tomorrow. I think the P0700 was just a blanket TCM code. I dont have a code reader for TCM codes..

I feel like i have been going down the rabbits hole here. I replace one thing the codes tell me it doesnt fix the problem then alerts me to another, and another... Im hoping that when I replace this PCM it will finally give me a solution. This is a great car and only 103,00 on it and im too invested to just give up now. Going to head back to Junkyard to hit up the 96 Ex i found and get that PCM I think.

 

Make sure you post all the codes before purchasing a PCM. This may lead you into a different direction for testing.

The PCM is the last component when doing diagnostic work.

Also check the simple stuff like the transmission fluid.

 

I had replaced about a quart of Tranmission fluid. I read somewhere if its an older vehicle you dont necessary want to replace all the fluid especially since Im not sure if it was ever kept up on. The transmission fuid I did remove was kinda black didnt see very much red in it. Should I replace all the fluid ????

I am going to try and get it back on comuter today for the codes. I am right now in the process of resetting the PCM but I did this a few days ago and it didnt work. However, that was before I replced the 2 selenoids so maybe this could work. I pulled the 7.5 raido amp and the 20amp ECU should I haver not pulled the 20amp ECU???

I was able to get the radio code watched a YOU TUBE video how to pull the radio and got the serial number from the back of it. Went to the honda site and entered my VIN # and Serial # of the radio and they emailed me the code. But it keeps making me enter the code everytime i turn on the car.

 

Got your PM. Better to do this in the thread, again more people will see it and we can keep all the conversations in one place.

Again, you can try resetting the codes and see if they come back. It the trans is slipping you will trip codes - the differences in rpm's between sensors will throw the P0700.

If the trans fluid was that "black" there is a chance that the trans is done for. As PA said, replacing the TCU is one of the last things you want to "try".

 

I'd probably try changing out the transmission fluid. Drain and fill the fluid (about 3 quarts) then drive the vehicle, or at least try to drive it. Then do two more drain refills.

You can use Dextron II fluid in your transmission (or equivalent) to save you some money.

 

Ok guys
I reset the PCM then drove to my mechanics shop. I started out in D3 and it seemed to cycle through 1,2,3 great. So I slipped it into D4 and gave it some gas and it it kind jumped into 4th then downshift ed itself. Throw it back into D3 and made it to the shop without it putting itself into neutral. We were at the shop awhile and put the computer on these are the codes.
P0141
OXYGEN SENSOR HEATER
CIRCUIT BANK 1
SENSOR 2

P0705
TRANSMISSION RANGE
SENSOR CIRCUIT.
MALFUNCTION ( 2 POSI)

So what do I do with these??
Also on my way home it will now only go from 1st to 2nd will not go into 3rd. Then after about 15 minutes will slip itself back into neutral again. And to boot I got a screw in my tire today. My luck can only go up from here.
PLEASE HELP