2002 Neon ATX Troubles

slow-mo · Post by **slow-mo** » Wed Nov 25, 2009 9:06 am

So the other day I drove to the store and all was well. When I came out, started my car I noticed a bit of a jerk when I put the car into reverse. As I put it in drive again a jerk then when I started to pull away the check engine light came on. I stopped, turned the car off and did the on-off to see what the codes were. P1684 and P0700...so everything was fine I went home and no issues. The check engine light ended up going off on its own. Same thing happened on my way home again a few days after this, only this time it went into limp mode. I went out the next day to work on it, started it up and sure enough the light went off and the car shifted just fine. Then yesterday it starts it again, same thing. I just haven't had much of a chance to look into it, but I'm going to try and get it scanned today. I've noticed though that every time this happens it's after I've driven the car for at least 20-30 minutes (drives/shifts just fine at this point), shut it off, and started it up again. I also notice that there is always a really hard shift/jerk when pulling the car from park to drive/reverse then the car goes into limp mode and the CEL comes on. As I mentioned I'm going to try and get it scanned today to see where to go, but does anyone have any ideas on what I should check in the meantime? Fluid color/level looks good and speedo doesn't seem to be out of whack so I'm not sure what more to "check." Thanks.

Panhead · Post by **Panhead** » Wed Nov 25, 2009 9:20 am

viewtopic.php?t=46603

it could be your tcm thats bad. lately, theres been a few of those.

slow-mo · Post by **slow-mo** » Wed Nov 25, 2009 11:34 am

Yeah I've noticed that as well. I actually did search some things, but I figured that I needed to get it scanned, unless you can visibly tell if the TCM or Solenoid is dead. So far this is the "could be" issues I've found:

TCM
Solenoid
Fluid level/color
Clogged Filter
Speed Sensor

I've had the battery/alternator tested just in case the P0700 code was coming from a drop in voltage. I think I've just come to the conclusion though that the P1684 code is a big bunch of BS lol, as it shows up even if the battery hasn't been disconnected. I believe there's a few more things that it could be, but I'm really looking for something I could check before making any unnecessary replacements and wasting money, before I get it scanned. Thanks for your input though.

Panhead · Post by **Panhead** » Wed Nov 25, 2009 6:41 pm

P1684 is a faulty code, i think. Its not listed in my Trouble Code Book. P0700 is Transaxle Control System Malfunction. out of the 5 things you mention, it only relates to 3 things, TCM, Solenoid and Speed Sensor. if you ran low on fluid, you will know.

slow-mo · Post by **slow-mo** » Wed Nov 25, 2009 11:31 pm

P1684 is supposed to be something to do with the battery being disconnected within the last 50 starts -- might be wrong though. Ah ok, I didn't know that. That helps much thanks for narrowing it down to 3 for me, it seemed to be limitless there for a while.

Panhead · Post by **Panhead** » Thu Nov 26, 2009 12:02 am

no problem. post what the problem was.

slow-mo · Post by **slow-mo** » Fri Nov 27, 2009 6:47 pm

So today I took my car to orielly's and decided to get it scanned while picking up the speed sensors. It came up with:

P0605
P0700

From my understanding, P0605 means an internal error in the TCM. So I'll be looking for one of those. Any suggestions on where to find a replacement? I figure the junkyard and I'll call around tomorrow. If I'm SOL though, any retailers besides the dealer? Dealer wants $773.65 -- OUCH.

Also, how the @#$% do you get those damn speed sensors off? There's absolutely no good angle to get to them.

Sometimes I hate my car

EDIT: Does anyone know what years are interchangeable with mine as far as the TCM goes? It's a 4-speed auto.

Post by **occasional demons** » Fri Nov 27, 2009 8:35 pm

For neons, 2002 only (Domestic market: exports had the 41te in '01 also)

Now, the separate TCM for the 41te was used in other cars in the 1990's, but IDK if they are compatible. The connector may have changed(?) I would check with the service department at your local dealer to see if other years will work. You will definately need the quick learn, and pinion setting procedures done, if it comes from another car. (If one from the older cars will even work)

'03 - up are integral to the PCM, so that is why '02 is the one year available.

slow-mo · Post by **slow-mo** » Sun Nov 29, 2009 6:03 pm

Yeah seems 02 is my only option.

Seems this is a dealer only part as well, unless I can find a used one at a Junkyard. So far no luck...not 1 single 2gn neon at pick n pull yesterday...almost everyone else was closed, so I'll call this week.

I have a post up in the WTB section as well, so if anyone has one PM Me thanks.

Panhead · Post by **Panhead** » Sun Nov 29, 2009 7:50 pm

do you have the part number in hand? might be able to get away with ordering it from www.wholesalemopar.com

slow-mo · Post by **slow-mo** » Sun Nov 29, 2009 9:30 pm

I don't have it, forgot to get it when I called, DOH! I tried looking there as well using a keyword search, but no luck. I'll have to call the dealer and try it again. Unless someone here has it?

slow-mo · Post by **slow-mo** » Mon Nov 30, 2009 5:06 pm

So I called the dealer again and it turns out the first guy quoted me the cost of the ECM lol...the actual cost of the TCM, R5034002AC EATX Module is $342.50, which is quite a bit better than nearly $800. Wholesale Mopar has it for $274 with a $125 core, so I'll likely order it there as finding it used seems to be futile at this point.

slow-mo · Post by **slow-mo** » Thu Dec 10, 2009 8:52 am

Finally got the part yesterday, right after it rained/snowed/froze all damn night. It's so @#$%ing cold right now it's ridiculous, and I have no garage to work in! Anyway -- does anyone know roughly how long this should take? I'm trying to gauge when I can do it and how long I'll have to freeze my ass off

Panhead · Post by **Panhead** » Thu Dec 10, 2009 11:22 am

Well, the TCM is located on the passenger side, near the washer fluid bottle. So what you need to do is take the front bumper off and its right there.

slow-mo · Post by **slow-mo** » Sun Dec 13, 2009 5:56 pm

Well so I managed to get it changed out and so far all is good. Shift points between 2nd-3rd seems to be a little longer than before, but it shifts nicely.

Is it really necessary to take it in for the pin test? I thought I read somewhere that it wasn't, but I can't seem to find it.

Also, I removed the splash shields from below and loosened the fender shield then I removed the passenger headlight. It gave me enough room to remove the bottle and TCM. Unfortunately I had 2 seized bolts on the TCM that snapped

...so I'll be taking it apart again when I can get the replacement bolts.

Thanks guys for the help, I'll send an update in a few days after giving it a good test.

slow-mo · Post by **slow-mo** » Wed Dec 16, 2009 7:43 am

Well it's been a few days now and the car seems to be running great. Feels better than it has in a long time actually...might just be placebo, might not

....

What's a little odd to me is that my car used to idle rough sometimes after coming to a stop at a stoplight, which has stopped with the replacement of the TCM. I had a previous post about this and thought it was the TPS...I never got around to replacing it then all of this started happening, so I dunno. I used to get some vibration as well around 60-70mph, which has gone away. And my shift points seem to be straightening themselves out, again might just be my imagination lol.