'94 Tranny won't shift out of low

[CobraCDN]

Well when it rains it pours I guess lol.

Driving on the highway today had the cruise set, and all of a sudden it was if the tranny had shifted itself into nuetral. I caught it right away as the RPMs of course rose considerabley and hit the brake to dissengage the cruise. as we slowed to about 60Kms/Hr (about 40 miles/Hr) the tranny went into low, by itself. It will not shift up from low now. Reverse works well, low works well also. Fluid is clean.. real clean, No noises, no slipage, no smells, car has 176,000Kms on it, prior to this instance the upshifting was normal. This car has never been driven hard and has been well taken care of. Seems to me maybe a module. Perhaps the Tranny control module or also called eatx I think?

Reason I think this is I heard of an Intrepid same symptoms, and the dealership replaced the module in 10 mins and he drove it away. all was fine.

I sorta fear taking it into a dealer, as they seem to be known for replacing a little to much in a lot of cases. Any suggestions would be appreciated.

Cheers

[theFREAKnasty82]

your car is in limp mode, where it won't shift out of second gear once it has detected an electrical fault. Did your speedometer ever quit working? If it did, your problem lies in that you have a faulty output speed sensor. If you can, try to old key method to see if there are any codes that came up by turning the key on/off 3xs ending in the on position the check engine light will flash, if it flashes twice then pauses then flashes another 4xs that's a code 24. If you need a definition as to what the code means, go here.

[CobraCDN]

No engine codes come up. There are however codes in the TCM which I can not retrieve. I cleared them by dissconnecting the battery for 10 mins. The result was the car ran fine.. tranny shifted fine. for a time about 80 kms. Then back to limp mode it went. The speedo never quit working. Is there any way for me to tell if the Solonoid assemmbly is at fault? Where is it? Easily changed? Oh and I did switch out the eatx relay with a known good relay, no change.

FREAKnasty your not Longknife from the HH chat rooms from days gone by are U?

Cheers

[theFREAKnasty82]

[quote=FREAKnasty your not Longknife from the HH chat rooms from days gone by are U?

Cheers[/QUOTE]

No my friend, I am not. To be honest, I don't go on too many chat rooms, just don't have time to sit in front of a computer for hours and talk.

To change out your solenoid pack is not easy as it involves you removing the transmission oil pan, and valve body to gain access to the solenoid pack. Honestly, go to a shop and have them check that out, personally a Chrysler dealer. At dealers, we have the Chrysler DRB III scan tool that can test your solenoids for any malfunctions that can occur. I'd strongly recommend that, though it's somewhat pricey, at least a factory-trained tech can narrow down the problem instead of a backyard mechanic hitting & missing trying to fix your problem.

[CobraCDN]

Thx, I'll take it to Chrysler today. I had cleared the codes again (2nd time) so I hope it will fault again on the way, or we will maybe drive it around untill it does lol. I'll post back when we know something. Thx for your help
Cheers

[Mira_cz]

please write how it goes. I have the same problem with my Concorde. I bought new tranny and it started with limp mode same way as previous. It helps to start and swich off engine several times (4 times mostly) and it runs well whole day (when car is warmed up).

[CobraCDN]

I did take it to the dealer. I had cleared the codes by dissconnecting the battery for 10 mins, which brought the tranny out of limp mode and it ran as normal, shifting great like it had before. One problem with that.. the dealer could not get any results from scanning for codes, as I wiped it all out. Apparently these computers keep info from the last 50 starts in memory. On top of that it did not go back into limp mode after putting about 200Kms on it. So to the dealer, all seemed fine.

So with the information I had researched, and a lot of advice from Freaknasty here (Thx bro) I got the dealer to flush the tranny install a new filter and put in ATF +4 fluid. ATF+3 would be ok but I figured may as well go with the best. ATF+4 is a synthetic hybred fluid I believe.

I now have just about 1000Kms since the fluid change and all is well. We're pretty much back to trusting the car for a long trip again. I'm suspecting the last owner of this car (We've only had it a month or so) may have had the fluid changed, and maybe did not have the correct fluid in it.. as these transaxles are apparently very picky that way.

I'll repeat FREAKnasty's advice on this one folks, take the thing to the dealer in limp mode and have them do a scan. Don't erase the fault codes! The dealer here charged $50 Canadian to perform the scan. Normally with stored codes in the TCM it would be worth the $50. Tranmission flush and ATF+4 (Most expensive fluid lol) came to about $200.00. They will not force you to do anything more if they scan & find fault with something. lol.

If it fails again I'll post the info.

Cheers

[CobraCDN]

Well it happened again... this time it went into limp mode about 1000Kms after the last time. Nothing out of the odrdinary.. ran fine parked it, this morning it was locked into second again when my wife took it out.

Sooooo, where to go from here. Could take it back to the dealer and get them to again scan it for another $50... Thing is I'm thinking it is not mechanical, meaning probably not the solenoid pack. Speedo is still working ok so not the speed sensors either. I guess this leaves the TCM (Transmission Control Module) or a communication prob (lose plug). Things that really baffles me is the shifting is nice, even the mechanic at the dealer said it's shifting perfectly when not in limp mode, and the fact that the amount of Kilometers driven between is very erratic... 200K one time then over 1000K this last time.

Does anyone know if the dealers can simply test the TCM regardless of wether it has stored codes or not? Is there some sort of diagnostic that can do this? My gut keeps telling me it's a faulty TCM.

Cheers

[theFREAKnasty82]

Cobra,

If you want to venture back to the dealer ask them to check the CVI (Clutch Volume Index). Ask them also for readings as to what they are here's what's normal CVI readings for your car:

Low/Reverse= 35 to 85
Overdrive= 75 to 150
Second-fourth= 20 to 77
Underdrive= 24 to 70

If the numbers are on the higher end, your clutch packs are worn and a transmission rebuild is more than likely. A Chrysler tech who checks transmission issues can check the solenoid pack manually by activating each solenoid. I think your problem may be that you need to have your TCM flash programmed. Flashing a module will update its operating parameters and correct any inconsistencies that may lie inside the module. I'd strongly suggest giving that a shot, slightly cheaper to do that then replace the TCM altogether.

[CobraCDN]

Ok, I found a TCM at another dealer an hour away, for some reason their price on it was $60 cheaper then any other chrysler dealer I called, and I've been wanting to pin this whole prob on the TCM from the start. I dunno why, I just did lol, so I went and grabbed it $327 CAD taxes included.

It is installed as of this morning, I took it for a quick ride (only about 8 Kms) and it seems fine again. Speedo works so I assume that I do not have to take it back to the dealer for a "Learning" procedure from a DRB. If it goes back into limp mode again . I'll have to take it back to the dealer, as I believe the only other possibility is the solenoid pack. I had read of another concorde driver that got a faulty solenoid fault code from the TCM, he got the solenoid pack replaced and the car did the same thing, back into limp mode. They replaced the TCM and he has not had a prob since. Seeing that I had already got the tranny flushed and ATF +4 put in, I hated to take it back to the dealer for fear I would be replacing solenoid pack for nothing and losing the new oil.

We will see.. time will tell lol Thx FREAKnasty, as soon as I saw you willing to blame the TCM I jumped on that hehehehe. I'll post back in a week or so and let you know whats happening, or sooner if it fails again.

Cheers

[CobraCDN]

Originally Posted by Mira_cz

please write how it goes. I have the same problem with my Concorde. I bought new tranny and it started with limp mode same way as previous. It helps to start and swich off engine several times (4 times mostly) and it runs well whole day (when car is warmed up).

This does not seem to be the same prob as mine. I have the original tranny in mine.Once in limp mode it stayed in limp mode untill i cleared the codes from the TCM. I did this by dissconnecting the battery for 10 mins. You may want to try this and see if anything changes. You will however wipe all stored codes in the TCM, so the dealer will not be able to scan for any untill the faults have repeated themselves. Or take it to the dealer and get them to read the codes. Then have them clear the codes and test drive the car. This way they will have the info the TCM is holding. As freaknasty says above, you can also get the TCM flashed with the latest firmware.


One thing, it is reccommended that if you replace your Transaxle, TCM (Transmission Control Module or EATX), Solenoid Pack, Clutchplate and/or Seal replacement, valve Body replacement or Reconditioning of the Valve Body, that you get a Quick Learn Procedure done on the TCM. This is done by use of the DRB Scan tool the dealers have.

I assume your car is in Limp mode? Nothing but second gear for forward motion? I don't think it should be so intermitant in and out of limp mode, I've read forums all over and have not seen that anywheres.

I would speculate you may have a communication problem/wiring problem, check your connections. Did it shift properly at all after the new tranny was installed? Who installed the tranny?

Cheers

[theFREAKnasty82]

Cobra,

you are correct my friend. It's best to check the connections going to the TCM, make sure the terminals aren't spread and corroded in addition to checking all grounds on the body/frame. I have seen many times of driveability issues due to bad connections and/or bad ground(s). Thank you for advocating what we Chrysler techs have been trained to look at & see. Please keep me informed as to what happens with your car.

Daniel

[CobraCDN]

Originally Posted by theFREAKnasty82

A Chrysler tech who checks transmission issues can check the solenoid pack manually by activating each solenoid.

Just a quick note I did contact the dealer that tried to scan... the tech did indeed actuate the solenoids but did not check the CVI's. Thus makes me feel a bit better. We'll keep driving and see

Cheers

[ed4733]

Originally Posted by CobraCDN

Just a quick note I did contact the dealer that tried to scan... the tech did indeed actuate the solenoids but did not check the CVI's. Thus makes me feel a bit better. We'll keep driving and see

Cheers

Ok. Now from what I read here, the TCM can be reset and the car should drive correctly for some short time? Cobra replaced the TCM and so far so good? I did get to check my codes in the Intrepid, they came back 55. I did clean the battery teminals a couple of weeks ago so that's the reason I did not get any error codes from the engine. The speedo did not go out on the car, so the speed sensors I hope are OK. I am dealing with a car that is not registered with the State of Louisiana (Confusion) so driving for long periods is not possible for a couple more weeks. Also why I have not gotten the car to a dealer yet although they have one 2 blocks from where I work. For now I am going to disconnect the battery for a day or two, and maybe replace the trans oil with ATF 4. I know we put ATF 3 in the transmission when we installed it in the car. Thanks for all the help guys.

Ed

[CobraCDN]

Originally Posted by ed4733

For now I am going to disconnect the battery for a day or two, and maybe replace the trans oil with ATF 4. I know we put ATF 3 in the transmission when we installed it in the car. Thanks for all the help guys.
Ed

So far so good with the Concorde, But it will be a week or so before we get a thousand Kms on it. The TCM loses it's memory, so yes it should come out of limp mode, but if there is indeed a problem in the tranny it should go right back in as soon as the conditions of the fault repeat themselves. When I cleared mine, I paid very close attention as to what the tranny was doing... meaning I kept the radio off so I could hear for any odd noises, I drove it very gently, paying attention to how it was shifting... remembering the whole point of Limp mode is to protect the tranny from further damage.

What I am not sure about is if you can mix ATF +3 & +4. If you can't then you will require a powerflush of the tranny. Perhaps someone can comment on that.

Cheers