Greetings from the UK, I am rather a disgruntled chrysler owner in the UK. I have had my neon for 10 years, and hardly used it. Its only done 30K miles from new with 2 services being done by chrysler.

All of a sudden my car has developed the dreaded p0700 and p1684 fault codes.

Things I have tried so far, have been checking the eatx fuse, and replacing the eatx solanoid.

Unfortunatly here in the UK the price of chrysler cars has plumited and these cars these days are only worth £1000 in A1 condition. I am looking for things I could try to get it back ontheroad that are simple things to try. I am an electronic engineer by trade so I understand wireing etc.

The car tax has expired also which is a further £260 a year. So this repair needs to be a cheap one, or this is another dodge off the UK roads to the scrap heap. I hope you guys can help.

I do have eng light on, and its in limp mode. It will sometimes go into 3rd with a huge leap forward, then an imediatly steps back down and well rev into the red if I let it.

 

P1684 is a pointless, useless, meaningless code. Don't worry about it. However, P0700 simply means there are fault codes stored in the TCM. You need to get the TCM scanned with a real scanner. Judging by how long you have had it, you do not have a 2003+ Neon...correct? What year is it?

 

That is correct its a late 2001 model with the 4 speed gearbox. I wish I could get the car scanned, but there is nobody within a resonable distance with the right kit to do the job. With these cars having such a bad name here, most dealers are out of business or changed to other manufacturers so thats a tricky one.

A chap did put something on it, and he said the code indicated 3rd and 4th gear problems. However I am not totally sold on that idea as its in limp mode.

 

Could someone also post on here where the earths are to the transmition, and an splice point for supplies to the TCM. For a car of this age with not much use I am going to hazzard a guess and get my hands dirty cleaning all the conections from the PCM and the TCM. This at least is a cheap attempt at a fix? what do you think

 

Unfortunately, without scanning the car, you'll just be throwing money at it. It could be a few things that cause gear ratio errors. Not sure why you aren't sold on it being gear problems? Any major transmission problem like that will cause limp-mode. That's the whole point of the limp-in mode...to try and prevent major damage.

 

I dont want to belive its the gearbox totaly is because I really want to save the car from being crushed. If I start to think the gearbox is shot I will have no choice but to have it crushed as its impossible to repair them at a resonable cost here in the UK. I am willing to spend some time and a little bit of money to get the car back on the road. Parts are a nightmare to get hold of here. For example if I want a solenoid pack I have to buy from USA pay a crazy amount for shipping over $100. I dont want to even go down that road until I know 100% that is the issue. I am willing to try things myself in the vein its something simple. Please trust me when I say here I am trying to save the car. I cannot even get hold of the filter kits here for the gearbox without going to the USA and waiting weeks for it to arrive. At least with the electrics its something I can dabble in myself. I spoke to the computer guy and he told me it came up with a TCM fault, Gear 3 and Gear 4 error. He said he will stick it on again for me tomorow afternoon.

 

I wasn't even aware that car came with a 4 speed automatic transmission...I thought they all came with a 3 speed trannies and a locking converter, or 4 speed manual.

Anyway, the reason I'm posting to this thread...I had the same error code (gear 3-4 error), but when my mechanic buddy used his scanner to read it, it didn't show gear 3-4 error, it read "no voltage to TCC solenoid", which basically turned out to be a bad TCC solenoid, shorted internally and no longer locking the converter up.

The solenoid was $13, and it took me less than two hours to install (valve body has to come out), including the time it took draining and refilling fluid.

 

I have done some more invistigation, I cleared the codes stored and went for a drive it was running perfectly 1st into 2nd, soon as it tried 3rd eng light came on and P0700 came back.

I have also smelled the fluid and checked the levels. With the engine cold its above the holes on the stick, and it does smell oilly which might indicate its burned. I guess that means big trouble. The guy said he would plug the computer back into it again to get me more specific codes. It would be really awsome if it is the solenoid pack as I thought these where sealed units. How did you get into yours to change just the 1 solinoed?

 

Pulled off the pan, took the valve body down...it's right under it, very easy to get to once the valve body is lowered. This is actually the TCC, or Torque Converter Control solenoid. It's what locks the torque converter after the car shifts into highway gear. The car will run and drive OK with this solenoid gone bad, it'll just use a little more gas because the motor will need to run at higher revs to make the same road speed.

Also, all transmission fluid is smelly, don't let that worry you. If it's burnt, it'll actually be more brown than red, I'm sure you'd have noticed if this were the case. I'm guessing your tranny is probably OK, if it turns out to be the same problem I had with mine.

 

The fluid is mostly red. Only shows signs of brown when I wipe it with a towel and even then its mostly red. I dont think I have same problem as you. Mine attempts to go into 3rd gear then realises it cannot for some reason then rinse and repeat lol

Have to be honest tho, to have a transmition fail like this on only 30K miles from brand new is a bit of a kick in the groin. I had a Pugeout do 200K miles before any problems manifested itself.