QuestionQUESTION: Hi Roland,
I have a 2002 Town and country,that ran fine until now.I started it,and all of a sudden the check engine light came on,then i noticed when i put the car in "R" it works.Put it in "D" it goes but does not shift out of the gear.The rpm's will go up,and so does speed but no shift.When i pulled over i checked the trans fluid in park with engine running and it seemed over full,when i checked it not running it checked to the line.Not sure why it not shifting,could you please help me out with this question,thank very much.
signed,A guy with 5 kids who needs help.
ANSWER: Hi Eric,
The trans has put itself into "limp-in" mode which the trans controller is programmed to do when some part/wire goes bad such that if the unit was allowed to shift it would damage itself unnecessarily. It is designed to keep you moving in 2nd gear only so as to get to where it can be corrected.
The best approach is to find out what fault it has noticed and recorded as a 4-digit number in its memory. You may well be able to read out that stored code using the ignition key:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch to odometer window to see if it changes from miles to show you any such numbers, preceeded by P. Let me know the numbers and we'll go from there. If that doesn't work, then an Autozone parts store will do a readout using a plug-in code reader for free, or an independent shop may do it for about $40.
But try the ignition key approach. Then tell me what they are and I can tell you what the possible causes/repairs are.
Roland
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QUESTION: Thank you for the quick response,
O.K. I checked the codes like you said with ignition,and first showed a "P 1684" then a "P 0700".
Not sure if this is important but about 2 months ago my speedometer quit working,everything else worked fine,for about a month.then it started working again out of knowhere.Not sure if any relevance with my not shifting.Again thank you so much,
ANSWER: Hi Eric,
The 1684 just means that at some point in the recent past the battery power to the engine controller was disconnected, not an issue that would impact the trans in any case. The 0700 says that there is a fault code stored in the trans controller, but that it has to be readout with a plug-in reader, evidentally. I say evidentally because I am a bit surprised that it didn't give you that specific other code as well, but let us assume it is correct and is just playing 'hard to get'. I would suggest having a readout with a plug-in OBD-II code reader, so see if you can get it free at Autozone or check around to independent shops to find the lowest price for a readout.
The loss of speedo function is indeed relevant, as there is what is called the output speed sensor on the side of the transmission that faces the front of the van, at the very far end, which is necessary to provide speed info to the speedo and also to cause the trans to shift properly. If it fails it should show a 0720 code and go into limp mode. If the speedo isn't working now that is a good bet to be the answer to the problem, but if it is working then do get a code readout done.
The sensor is variable in price depending upon where you buy it (ranging from $25-80), and you can remove and replace it yourself if that turns out to be what is required to cure the limp-in mode.
I'll wait to hear back from you.
Roland
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QUESTION: Good morning ,
Got those codes off the plug in at Autozone,the first read "P0700" (BB1-shorted or open circuit within transaxle),(BB2-failure of transaxle control module).
The 2nd read,"P0605"(BB1-shorted solanoid or sensor within transmission),(BB2-shorted electrical circuit),(BB3 failed TCM). That was it.Thank you for your help thus far.
AnswerHi Eric,
If the speedo is working then my earlier emphasis on the output sensor in no longer an issue. The '02 manual says for the 0605 code "Transmission control module ROM self test fault detected". This implies, from my understanding but with no guarantee, that the transmission control module itself is the problem. So looking for a used one at a wrecking yard, taken off a similar minivan ('02 would be the best match) with the same 41TE-type transmission, may be the first action you would want to take.
It is located in front of the left front wheel housing. You have to remove the left tire/wheel, then pull back the splash shield itself at the front of the wheel well and you will find it bolted to the frame in that far-forward position. It would be good to have a shop verify the pinion setting (calibrates the speedo) and do a 'quick learn' procedure using a computerized diagnotic box after the unit is installed. That will make sure the speedometer reads properly and the transmission shifts optimally from the get-go. But the trans will 'self-learn' slowly if you don't want to spend the money on that labor. Let me know if you can't find it, or want specifics on the replacement procedure. There are several pages in the manual that show exactly how to remove and replace it, which I could xerox and postal mail to you.
Roland
